Category: Chemistry

Introduction

Poly halogens can be broken down into subgroups. Due to their widespread use, important poly halogens include Freons, DDT, and carbon tetrachloride. Carbon tetrachloride is a colourless, combustible liquid with no discernible odour. Commercial and household use of carbon tet as a cleaning agent was popular before 1970.

Users are put in danger when these refrigerants escape into the air. This calls for the development of innovative, safe, and non-toxic refrigerants. DDT (dichloro-diphenyl-trichloroethane) was developed in the 1940s and was the first of the modern synthetic pesticides. It was first employed to treat military and civilian populations for insect-borne ailments, including malaria and typhus.

Polyhalogen Compounds

Polyhalogen compounds are those that include several halogen atoms (elements in group 17 of the modern periodic table). In both manufacturing and farming, poly-halogen compounds are a common staple. They have several applications and are widely employed as pesticides, solvents, and anaesthetics.

There are several important poly-halogen compounds, but some of the most well-known are methylene chloride, chloroform, carbon tetrachloride, iodoform, DDT, and benzene hexachloride.

Freons

Freons, or chlorofluorocarbons, are a popular refrigerant. Fluorine and chlorine atoms are substituted for the hydrogen atoms in methane  (\(C{H_4}\)) to produce it. The properties of CFCs may be altered by including different numbers of chlorine and fluorine atoms. The rule of 90 is used as a naming convention for chlorofluorocarbons. The CFC is commonly referred to as CFC-n, where n is any of the numbers listed below. Following that pattern, we may deduce n by subtracting 90 from the total number of fluorine, hydrogen, and carbon atoms given. If, for example, a CFC’s formula is \(CC{l_3}F\), then that CFC is designated as CFC-11.

Freon Structure

Structure

Molten sodium and heated, concentrated mineral acids have no effect on Freons. Therefore, as the ratio of fluorine to carbon atoms in Freon gas increases, the length of the resulting solid C-F bonds decreases. C-F bond lengths range from 1.29 to 1.358 angstroms for molecules like  \(C{H_3}F\), \(C{F_2}\) etc.

Synthesis

Antimony fluoride reacts with carbon tetrachloride to produce freon and Antimony Chloride, which acts as an autocatalyst. 

To create chlorofluorocarbons, chlorinated methanes and ethanes are commonly subjected to a halogen exchange reaction. The process of converting chloroform into chlorodifluoromethane is outlined below..

Uses

Due to their low boiling points and low viscosity, freons are widely used as refrigerants in:

• Mechanical cooling and refrigeration devices
• Aerosol propellers
• Ingredients for Foam Blowing
• Solvents
• Glass and intermediate polymer coolers
• Inhalants are widely used legal medications that are ingested through the respiratory system. Inhaling gasoline, paint thinners, sprays, or refrigerant gases is a common way to get high.

DDT

The chemical formula for DDT, or dichlorodiphenyltrichloroethane, is \({C_{14}}{H_9}C{l_5}\). This chemical compound is a crystalline solid that is odourless, tasteless, and colourless under typical pressure and temperature conditions.

In 1939, Swiss chemist Paul Hermann Müller developed DDT’s insecticidal properties. In the latter years of World War II, DDT protected civilians and military personnel from insect-borne diseases, including malaria and typhus.

Structure

DDT is composed of 2 phenyl groups with five carbons as substitutions. The chemical formula of DDT is \({C_{14}}{H_9}C{l_5}\). DDT and its IUPAC name is 1,1,1-trichloro-2,2-bis(p-chlorophenyl)ethane. 

Synthesis

To produce DDT, a mixture of chloral and chlorobenzene (in a ratio of 1:2) is cooked in strong sulfuric acid.

Uses

In addition to solutions in xylene or petroleum distillate, DDT is also available as emulsifiable concentrates, water-wettable powders, granules, aerosols, smoke candles, vaporisers, and lotion charges. Agriculture made heavy use of DDT between the years 1950 and 1980. Fifteen different firms around the United States worked together to produce it. DDT was also used inside structures as a pesticide. Malaria, typhus, body lice, and the bubonic plague were some diseases it was used to combat.

Carbon Tetrachloride

The chemical tetra chlorocarbon was created in a lab; it does not occur naturally. It’s a transparent liquid with a barely discernible sugary scent. Benziform, perchloromethane, methane tetrachloride, carbon chloride, and methane tetrachloride are some of its alternate names. Carbon tetrachloride is a colourless gas that regularly floats in the air.

Structure

The Lewis structure of carbon tetrachloride consists of a single carbon atom in the middle, surrounded by four chlorine atoms. Molecular \(CC{l_4}\). and its electron geometry are both tetrahedral in form. A bond angle of 109.5 degrees is found in \(CC{l_4}\).

Synthesis

French chemist Henri Victor Regnault figured a combination of chloroform and chlorine to produce carbon tetrachloride:

Uses

The various uses of Carbon tetrachloride are:

• Tetrachlorocarbon is used as a solvent in pesticides.
• Fire extinguisher and degreaser
• Remover of Spots
• Making propellants for aerosol cans and cooling fluid.
• As a result of the harm they cause, only a small number of industrial uses are allowed.

Summary

Carbon compounds with more than one halogen atom are referred to as poly halogens. Polyhalogen compounds include freons, DDT, and carbon tetrachloride, amongst others. These poly halogens can be utilised in a variety of contexts. While Freons are used to produce refrigerants and aerosols, DDT and carbon tetrachloride are utilized in the agriculture sector as effective insecticides.

Frequently Asked Questions

1. What effects are associated with the exposure of Freons to UV light?

In the event that Freon does in fact include atoms of chlorine, the chlorine that is extracted from Freon by UV light forms a chemical connection with ozone.

Because of this, ozone cannot quickly revert back to its natural state, which leads to the destruction of ozone and the formation of ozone holes in space.

2. How is DDT toxic?

DDT is toxic because it causes severe diseases in human and animal bodies when ingested. It can cause growth defects, and reproductive issues, it is carcinogenic and it can also cause nervous diseases. 

3.What environmental act talks about carbon tetrachloride?

Carbon tetrachloride was a chemical that was used for dry cleaning and as a fire extinguisher before it was made illegal worldwide in 1987 under the Montreal Protocol. It damages the ozone layer and contributes to the ozone hole that has formed over Antarctica.

Introduction

One type of electrochemical cell is the electrolytic cell (EC), which converts electrical energy into chemical energy. This process causes an artificial redox reaction. Electrolytic cells may break down a wide variety of chemicals. It’s a technique for getting rid of ions in a mixture. The reduction half-cell and the oxidation half-cell together make up a single electrolytic cell. Energy for voltaic cells (VC) comes from a chemical reaction that happens naturally and results in a flow of electrons across a circuit (external). These cells are essential because they form the backbone of batteries, which provide the energy that runs modern civilization. Electricity is typically used to fuel non-spontaneous processes.

About Electrolytic Cell

It’s a device for electrolyzing a chemical compound, or breaking it down using an electric current. Simply put, this is a specific kind of electrochemical cell. Hydrogen (\({H_2}\)) and oxygen (\({O_2}\)) are produced when water is electrolyzed. Here, a bit of more power is required to get beyond the threshold energy level.

The electrolyte in these cells is often a fused or disintegrating ionic compound, and the cell itself consists of two electronic or metallic conductors (electrodes) that are either separated from one another or remain in touch with one another.

One of these is the use of a direct electric current source to link these electrodes, which keeps one of them negatively (-vely) charged while leaving the other, maybe positively (+vely), charged.

The cathode (-ve) moves the anode (+ve) and transfers one or more electrons to the cathode. This creates brand-new particles, either neutral or ions. Electron transmission is the determining factor in the cumulative effect of these two processes.

Galvanic Cell and Electrolytic Cell Comparison

Both electrolytic and galvanic cells function in the same way. There are three main features that make electrolytic cells and galvanic cells similar: Both cells need a salt bridge for proper functioning. Electrons (e-) always flow from the anode to the cathode, and both have cathode and anode components.

Difference Between Galvanic Cell and Electrolytic Cell

Electrolytic Cell Application

Some of the applications of electrolytic cell are

1. Generation of oxygen gas from water .
2. Electroplating
3. Electrorefining.
4. Electrowinning 
5. Isolation of metals of commercial importance such as aluminium, gold, copper, zinc, etc. 

Properties of Galvanic and Electrolytic Cells

Galvanic cells (GCs) are devices used to convert chemical energy into electrical energy. Electrolytic cells are capable of converting electrical energy into chemical energy. A salt bridge unites two segments housed in separate containers. The oxidation reaction takes place at the anode, and the redox reaction at the cathode. Electrons (e-) are supplied by an external cell and flow from the cathode to the anode.

Working Principle of an Electrolytic Cell

Electrolytic cells are instruments based on the idea that during an oxidation-reduction reaction, electrons (e-) are transferred from one chemical species to another.

Lets take the example of electrolysis of NaCl. 

Sodium metal and chlorine gas are produced during the decomposition of molten sodium chloride (NaCl).

Electrolysis occurs when a second energy source is applied to a vessel containing molten sodium chloride and carbon (C) electrodes. At the cathode end, the Na+ ion will be neutralised by the flow of electrons (e-) from the anode.

Although the anode and cathode retain their traditional roles, oxidation and reduction now occur at the cathode and anode, respectively. The electrolyte cell’s operational parameters are crucial to its proper functioning. Even the most potent reductant will succumb to oxidation. The most oxidising substance will be the one to be depleted.

The success of the Electrolytic Cell Molten sodium chloride (NaCl) depends on the electrolysis process, which is an integral part of the electrolytic cell.

Electrolysis of NaCl

Two non-active electrodes are submerged in a bath of liquid NaCl. Dissociated Na+ cations and Cl- anions are present here. The cathode is the part of the circuit where electrons (e-) gather when an electric current is sent through it. As a result, the resulting charge is negative (-ve). Because of this, the positively charged sodium (Na) cations go to the cathode, which is negatively charged. This results in the formation of sodium metal (Na) at the cathode.

Chlorine Cl atoms are transferred to the cathode during this process. It causes chlorine gas to be generated at the anode (Cl2). Two electrons (e-) are then freed, completing the circuit. In an electrolytic cell, molten NaCl is electrolyzed to produce Na and Cl2 gas, two metals (EC).

Summary

An electrolytic cell (EC) is a device that converts electrical energy into chemical energy via a non-spontaneous redox action. A reduction half-cell and an oxidation half-cell make them up. An electrolytic cell consists of the cathode, anode, and electrolyte. Similarities and differences exist between electrolytic cells and galvanic cells. As an example, the electron (e-) in each cell is unique. Understanding electrolysis requires familiarity with Faraday’s laws. The magnitudes of electrolytic effects are defined by them.

 

Frequently Asked Question

1. Define EMF?

Maximum potential difference between a cell’s electrodes is its electromotive force (EMF). The net voltage between the oxidation and reduction halves of a process is another way to think about it. The electromotive force (EMF) of a cell is the primary criterion for establishing the galvanic nature of an electrochemical cell.

2. What is the meaning of zero EMF in a battery?

After the chemical process within a battery is complete, the anode and cathode have the same number of electrons, and the electrical field between them is zero. When a reverse field is applied to a rechargeable battery’s contacts, the battery’s chemical makeup is returned to its previous state, allowing it to once again discharge electrons in an electrical circuit.

3. What is the relation between the current and the electrolytic product? 

The 1st law of Faraday says that the amount of electric current flowing through an electrolyte causes the same amount of chemicals to build up as the amount of current. Faraday’s law of electrolysis says that when the same amount of electric current flows through many electrolytes, the amount of materials that build up is proportional to their chemical equivalent.

Introduction

The chemical symbol for barium chloride is (\(BaC{l_2}\)). It has the appearance of a white salt but is actually an inorganic chemical complex. It gives flames a yellowish-green colour and emits poisonous fumes. It readily absorbs or absorbs water molecules, and may thus cling onto them. As a rule, it dissolves more readily or more easily in water. There is only cautious usage of it in labs and factories due to its toxicity. It has no discernible odour or hue in its pure form. 

What is Barium Chloride (\(BaC{l_2}\))?

The empirical formula for barium chloride is \(BaC{l_2}\). The only solvents that work on it are water and methanol, whereas ethanol and ethyl acetate have no effect. To purify the salt water used in caustic chlorine production plants. Sometimes, it is used in the manufacturing of heat treatment salts, which are used in the process of hardening steel.

Its extreme toxicity is shared by the majority of other barium salts that dissolve in water. It changes the colour of a flame to a bright yellow-green. Its molar mass, or molecular weight, is 208.23 g/mol in its anhydrous form and 244.26 g/mol in its dihydrate form (in dehydrated form). About 3.856 g/cm3 is its density. Barium chloride may be dissolved in the methanol, but not the ethanol or the ethyl acetate. When it is dehydrated, it takes on a shape that is similar to an orthogonal structure.

Structure of Barium Chloride \(BaC{l_2}\)

The anhydrous form of barium chloride has a crystal structure that is orthorhombic, while the dehydrated or monoclinic form is extremely unusual. Barium chloride (\(BaC{l_2}\)) is the ionic compound of  \(B{a^{2 + }}\) cations and \(2C{l^{-}}\)

anions. 

Barium chloride

Preparation of Barium Chloride

Following is the possible methods for the preparation of Barium Chloride (\(BaC{l_2}\))-

Barium sulphate is reacted at high temperature with coke to give barium sulphide.  

The barium Sulphide is further reacted with dilute hydrochloric acid as follows:

Properties of Barium Chloride \(BaC{l_2}\)

Some of Barium Chloride’s most fundamental characteristics are as follows:

• it takes the form of a white solid, although it can also take the form of a white salt
• Barium chloride has a melting point of about 960 °C.
• It dissolves in water and methanol but not in ethanol or ethyl acetate (EtOAc)
• Barium chloride’s molecular weight is 208.23 g/mol (for the anhydrous form) and 244.26 g/mol (for the dihydrate form) (in dehydrated form).
• The density of barium chloride is approximately 3.856 g/\(c{m^2}\) (in anhydrous form)..
• Barium chloride has a boiling point of roughly 1560 °C.

Uses of Barium Chloride \(BaC{l_2}\)

1. For the most part, barium chloride is used in caustic chlorine factories to remove impurities from brine solutions.
2. It is employed when carbon steel has to be hardened.
3. In addition, it is used in water purification.
4. The production of barium chromate, oil lubricants, and similar products all benefit from its presence.
5. Purification and the production of salts for thermal processing are two further applications.
6. In addition, it is crucial to the creation of some barium salts and a few dyes.
7. It may also be used to detect sulphate ions in a sample.
8. In the fireworks industry, it’s used to make the crackers a vivid yellow-green colour.

Chemical and Physical Properties

Chemical Properties

When we mix a solution of barium chloride with sodium sulphate, we get a twofold substitution reaction. A white precipitate, consisting of barium sulphate, will appear at the bottom of a test tube after the reaction. The diagram below illustrates the ionic reaction formed by this reaction.

The binary chlorine salt barium chloride readily interacts with water, as is well known. It forms NaCl-like ions when it dissolves in water. It doesn’t have any effect on the solution’s pH because of its neutral behaviour. The following is a response to that:

Physical Properties

• As stated in this article, Barium Chloride (\(BaC{l_2}\)) has an orthogonal crystal structure when anhydrous and a monoclinic structure when dihydrate or dehydrated.
• It has a white crystal-like appearance and a molecular weight of 208.23 g/mol (anhydrous) and 244.26 g/mol (hydrous) (in dehydrated form). The anhydrous form has 3.856 g/ml density, whereas the dehydrated form has 3.098. It melts at 963 °C and boils at 1560 °C.
• Barium chloride dissolves well in water and methanol but not in ethanol or ethyl acetate.

Health Hazards Caused due to Barium Chloride

Barium Chloride’s main health risks are:

• Barium chloride’s high toxicity limits its application in industry and labs.
• Barium chloride’s toxicity causes eye, skin, and mucous membrane irritation.
• Inhaling, swallowing, touching, or absorbing it might cause unconsciousness.
• Poisonous barium chloride can damage the kidneys, heart, and brain.
• Aquatic life is at risk.

Summary

Barium chloride (\(BaC{l_2}\)), an inorganic chemical compound, is a white solid or salt. Like barium salts, it is very poisonous. Water and methanol solubility.

It becomes yellow-green towards the flame. We then covered industrial or commercial barium chloride structure and processing. Its many uses include brine or saltwater purification, wastewater treatment, steel case hardening, and more. Finally, we addressed Barium chloride’s physical and chemical features and health risks.

Frequently Asked Questions

1. Is barium harmful to ecosystems?

Very little of these chemicals are preserved in this form after being released into the environment. Insoluble barium compounds have a longer lifetime in the environment and are usually harmless. The two most frequent forms of barium in nature are barium sulphate and barium carbonate, both of which are present in both soil and water.

2. Can barium be inhaled without risk?

A tiny amount of barium sulphate is safe for the lungs to absorb. Barium sulphate can disrupt pulmonary ventilation and perfusion, leading to symptoms including dyspnea, hypoxemia, acute respiratory distress syndrome (ARDS), and mortality if an excessive amount is inhaled or ingested.

3. As an electrolyte, why is \(BaC{l_2}\) so powerful?

\(BaC{l_2}\) is an ionic chemical that dissociates in water to produce ions and conduct electricity. Ionic bonding produces this salt. When electrons are shared between two atoms, an ionic connection forms.

Also Read this article on Barium Carbonate

Introduction

Molecular formula of barium carbonate This substance belongs to the class of inorganic chemicals. This has no aroma or flavour at all. It is a white salt that, like most other alkaline earth metal carbonates, is weak bases in water solution but soluble in most acids (except sulphuric acid). To put it another way, it is one of the most economically or commercially significant barium compounds. While insoluble in tap water, it dissolves somewhat or only partially in carbon dioxide-rich water (\(C{O_2}\)). When combined with other ingredients, it makes a potent rat poison. Other industries that put it to use include those that produce pigments, clay, polymers, plastics, etc. It’s also a key ingredient in making glasses of varying refractive indices.

What is Barium Carbonate?

The chemical formula for barium carbonate, an inorganic chemical substance, is (\(BaC{O_3}\)). In terms of flavour and smell, it’s completely neutral. It looks like regular table salt, just like the other carbonates of alkaline earth metals. It dissolves poorly or not at all in water, although it does so partially in water saturated with carbon dioxide . It also dissolves in most acids, including nitric and hydrochloric acid, but not sulphuric acid. The mineral form of this is known as witherite, and it occurs naturally. Many industrial and commercial applications exist for it. It’s a crucial barium chemical, actually.

Physical Properties of Barium Carbonate

Som physical properties of barium carbonate are-

• It is insoluble in pure water but it is soluble in the water-saturated with Carbon dioxide (\(C{O_2}\)) and it is soluble in most acids except sulphuric acid.
• It has a specific heat of around 0.1448.

• It generally appears as white crystals or white salt powder.
• It has an atom complexity of around 18.78.

Chemical Properties of Barium Carbonate

Some of barium carbonate’s chemical characteristics are as follows:

• Barium carbonate readily reacts with soluble calcium salts to generate Barium sulphate, which precipitates out of the solution, and calcium carbonate. Here is the chemical reaction that occurs while doing so:-

• Barium carbonate can also react with hydrochloric acid to precipitate out as  Barium chloride(BaCl), with by-products being water and \(C{O_2}\). 

Barium Carbonate Structure

      

Barium Carbonate

As seen from the above diagram, \(B{a^{2 + }}\) cation is bonded to the \(CO_3^{2 – }\) anion through an ionic bond. 

Various Uses of Barium Carbonate

Barium carbonate has a variety of applications, including those listed below.

1. As it has been discovered to be an insoluble white salt, it finds extensive application in the ceramics sector, where it is utilised in the production of many different kinds of ceramics.
2. Moreover, it is crucial in the production of PTC thermistors, capacitors, and other electronic devices, as well as the increasingly popular electronic ceramics.
3. Moreover, barium carbonate is used in the creation of fibre optical glasses and magnetic components.
4. It is also a key ingredient in the production of other barium compounds, such as barium oxide and barium peroxide.
5. A common method of producing rodenticide also involves barium carbonate (rat poison). It looks like flour or salt, which is probably why rats are drawn to it.
6. Barium carbonate has several commercial uses, including in the oil-drilling industry, photography, enamel production, magnetic material production, paint and brick production, and a wide range of chemical processes.

Production Method of Barium Carbonate (\(BaC{O_3}\))

Common production methods are:

Carbonation Method– In this process Barium Sulphide (BaS) is pulverised at high temperature. The reaction takes place as follows:

Poison Nepheline Conversion Method– In this method witherite is reacted with an ammonium hydroxide along with ammonium carbonate. The reaction takes place as follows: 

Metathesis Method– In this method barium sulphide and ammonium carbonate react to form barium carbonate through metathesis. The chemical reaction is represented as– 

Dry Granulation Method- Here, barium carbonate is sourced from overabundant precipitation, which is then sieved and stored in a raw materials warehouse.

Summary

Inorganic chemical compound barium carbonate is a  white crystalline powdered salt. Its molecular formula is \(BaC{O_3}\). It has no discernible taste or smell and no visible hue. In addition to being soluble in carbon dioxide-saturated water and the majority of acids, besides sulphuric acid, it may also be dissolved in pure water. It is important in various commercial industries such as polymer, dyes, paints, etc. Moreover, it is crucial in the production of PTC thermistors, capacitors, and other electronic devices, as well as the increasingly popular electronic ceramics.

Frequently Asked Questions

1. What makes barium carbonate so dependable?

Among common carbonates, barium carbonate has the highest heat stability. A metal’s electropositive nature tends to grow as it moves towards the bottom of the group of alkaline earth metals. As a result, they become more stable at high temperatures. The stronger the influence of the positive ion on the carbonate ion, the smaller the ion must be.

2. Does barium carbonate have any negative effects on the ecosystem?

As barium is insoluble in water and readily combines with other elements found in nature, like carbonate and sulphate, it presents minimal danger to humans and animals. Persistent barium compounds are often found in surface soil as well as the sediment of freshwater soils.

3. Would barium rust if left exposed to the air?

Barium is an odourless, silvery-white metal at room temperature that becomes a silvery-yellow tint when exposed to air. While it cannot be burned, it may break down when heated, releasing harmful chemicals.

Introduction

There are two types of acids, concentrated and dilute, both of which are defined by their concentration. Dilution occurs when an acid has a significant amount of water added to it. As such, they are diluted to lower the overall acidity. We stay away from the very dangerous acids. In addition, we pay special attention to acids because they may be kept in the home for regular use. Also, they are employed in the control of several chemical operations.

What are Acids?

To be considered acidic, a substance must have a sour flavour when dissolved in water, change the colour of certain indicators (like blue litmus turning red), react with certain metals (like Fe) to release H+ions, react with bases to generate salts, and speed up chemical processes. Acids can be either inorganic (such as nitric and phosphoric acids) or organic (such as phenolic and sulfonic acids) molecules. When these compounds are dissolved in water, the H atom(s) they contain are released as positively charged H+ions.

Examples of Acids

Examples of acids include the following:

• Arrhenius acid
• Citric acid
• Hydrochloric acid
• Sulfuric acid
• Acetic acid
• Vinegar

What is Dilute Acid?

If an acid has been diluted, it has lost more of its acidity to water than the water has gained from the acid. It does not weaken acid or reduce its reactivity. The acidity of the solution you’re working with will decrease. Dilute acids include sulfuric acid that is just 5 percent concentrated. The concentration of sulfuric acid in a solution of 100 grams of water is five percent.

Properties of Dilute Acids

Some common properties of acids are:

• There is a sour aftertaste while consuming acid.
• Electrical solutions are formed when water and acids are mixed together. All of the anionic charge is lost when strong mineral acids are dissolved in water. When organic acids are dissolved in water, a mild ionisation occurs. Some molecules are still in the process of joining together. They are referred to as weak acids.
• When exposed to acids, the litmus indicator changes from blue to red.

Chemical Properties of Dilute Acids

Hydrogen gas is created when metals react. Get some zinc flakes and place them in a clear test tube. Fill the test tube with a solution of HCl that has been diluted. The reaction produces a gas. A burning splitter is moved extremely close to the mouths of the test tubes in order to examine hydrogen gas. A popping noise can be used to detect the presence of hydrogen gas.

Salt & water are produced when an acid reacts with a base (metallic oxide).

When acids react with sodium hydroxide, salt and water are produced.

Altering the pH of the reaction environment can cause profound changes in the products generated from two extremely specific reagents.

Examples of dilute acids

Dilute Hydrochloric acid

Hydrochloric acid, often known as muriatic acid, is an aqueous solution of hydrogen chloride. The chemical symbol for dilute hydrochloric acid is HCl. The solution lacks colour and has a distinct aroma. Hydrochloric acid is a strong acid. It is a part of the stomach acid of most animals, including humans. Hydrochloric acid is a crucial reagent in many different industries and fields of study. Dilute hydrochloric acid refers to aqueous acid mixes in which the concentration of HCl is lower than that of water.

HCl molecule

Dilute sulfuric acid 

Sulfuric acid is a mineral acid made up of H2O and sulphur. Sulfuric acid has the formula\({H_2}S{O_4}\). Sulfuric acid is also known by the name “oil of vitriol,” which is a synonym. It is a thick liquid that is both odourless and water-soluble. With its hygroscopic properties, it swiftly soaks up moisture from the air. The aqueous form of sulfuric acid is a powerful acid.

Dilute acetic acid

Ethanoic acid is the official word for acetic acid. \(C{H_3}COOH\) is the molecular formula. It’s an acidic, odourless, and colourless organic molecule. Vinegar contains just acetic acid and water, with the acetic acid accounting for at least 4% of the liquid content. Acetic acid ranks as the second simplest carboxylic acid. The hydrogen in the centre of the carboxylic group is ionisable by carboxylic acids like acetic acid (COOH). Due of this hydronium ion release, acetic acid is acidic. Disappointing monoprotic acid quality.

Summary

Hence, acids are compounds that, upon contact with a base, give forth hydronium ions. Protons are donated to the body by acids. pH values below 7 are considered acidic. Substantial volumes of water are found in diluted acids. A concentrated acid can be diluted using water. A lot of hydrogen ions are released into the water when a strong acid is used. Inorganic acids such as sulfuric, nitric, and hydrochloric acid are examples of strong acids. These substances are called weak acids because they only dissociate into a small number of hydrogen ions when dissolved in water.

 

Frequently Asked Questions

1. What is the procedure of dilution?

Ans. Acid is always poured into the water and not the other way around during dilution.  When \({H_2}O\) is combined with an acidic solution, the \({H^+}\) ion concentration decreases, and the solution’s pH rises. The acidic strength then starts to weaken and it becomes diluted. 

2. Are diluted acids as hazardous as concentrated acids?

Ans. Although dilute acids are considerably less hazardous than concentrated counterparts, they are labelled with a warning that they could cause mild health problems or skin irritation. This makes sure that if one of them touches your skin, it will get red or blister.

3. How are dilute acids conducting in nature?

Ans. Dilute acids have free ions in the solvent. These ions carry charge from one electrode to another on application of potential and conduct electricity.  Aqueous HCl solutions can generate energy. Diluted acid produces fewer ions and conducts electricity less.

Introduction 

Ordinary substances like table salt are examples of binary compounds. Rock salt structure refers to the crystalline arrangement of salt. Sodium and chlorine ions are organised in a lattice pattern, which is made visible by this structure. Sodium and chlorine ions form a binary system in the sodium chloride lattice. It is essential to learn about these binary compound structures in order to comprehend the characteristics of various materials. Improved elasticity, strength, conductivity, and other physical qualities can be achieved through the synthesis and manufacturing of new materials in this branch of chemistry.

Structure of Sodium Chloride

What are Binary Compounds?

Binary compounds are those that consist of two distinct components combined together. Element refers to a material that cannot be chemically reduced to a simpler form. The simplest class of molecular compounds are the binary compounds. To further distinguish them, we might call them binary phase compounds or just binary phases. These compounds are crucial as they are used as building blocks in the production of several other key organic and inorganic chemicals. Water is an example of such a crucial substance. \({H_2}O\) consists of hydrogen and \({O_2}\), which are the two elements that may combine to form water. Water is a V-shaped covalent binary molecule. Two hydrogen atoms are covalently bonded to an oxygen atom with two lone pairs of electrons, making up a water molecule.

The Naming of Binary Compounds

Naming a binary compound is the same as naming any other kind of chemical. In the IUPAC system, you’ll find:

• To identify which cation is present in a binary compound, the cation’s name comes first.
• Binary compounds have their anion names written after the cation names.
• If you add the suffix -ide to the anion’s name, you get the element’s name. For instance, fluoride is the name for the fluorine anion.
• Among these, iron (II) oxide (FeO) is one example. Because iron’s oxidation state is +2, a roman number representing two is appended to the cation’s name.
• If there are more than two of each element in a binary complex, the ion count of each element is included in the ion’s name.
• Dinitrogen trioxide (\({N_2}{O_3}\)) is one such example. The prefix “di” is added to nitrogen because there are two of the element, while the prefix “tri” is given to oxide because there are three of the element’s oxygen atoms.
• When a binary compound contains a transition metal cation, the oxidation number of the cation is shown after the cation’s name in Roman numerals.
• Potassium chloride, for instance, is abbreviated as KCl. In this situation, potassium is a cation and chloride is an anion.

Examples of Binary Compounds

Covalent binary compounds-

Such compounds contain atoms of two elements joined by covalent bonds:\({N_2}O\) ,\(CC{l_4}\) ,\({H_2}{O_2}\), \(C{H_4}\), etc. 

Ionic binary compounds –

Such compounds contain ionic bonds that link atoms of two elements : NaCl, MgO, NaBr,\(BaC{l_2}\), etc. 

Transition metal binary compounds-

AuI, \(FeC{l_2}\)2, CuI, Lead (II) fluoride, \(PbC{l_2}\)2, etc. 

Binary Acids

Binary acids, also called hydracids, consist of hydrogen and a non-metallic element.  There are two types of acids: oxyacids and binary acids. Oxyacids are compounds made up of hydrogen, oxygen, and sometimes additional elements as well. The prefix “hydro,” followed by the element name, and then the suffix “ic” are used to name binary acids. Hydrochloric acid (HCl) is one such chemical. The primary building blocks of hydracids are hydrogen and halogens. Many parameters, including the bond energy of bonding between anion and hydrogen, the solvation energy of anion, anion electron affinity, etc., determine the potency of these acids. The hydrogen-ion connection is weaker in acids because hydrogen is a more electronegative element.

Difference between Binary Acids and Binary Compounds

Binary Ionic Compound

Binary ionic compounds are those that consist of atoms of two different elements bound together by electrostatic repulsion. For example NaCl, \(BaC{l_2}\), etc. These compounds form conduction solutions because of free moving ions. 

Summary 

In chemistry, the fundamental building blocks are binary compounds. Learning about larger molecules and compounds is easier after establishing a firm grasp of these simpler ones. There is a large variety of uses for these chemicals since this class of compounds is so vast. For example, a binary compound might be a binary covalent compound, a binary ionic compound, a binary acid, a binary transition metal compound, etc. Pharmacy,organic chemistry, analytical chemistry, industrial chemistry, materials chemistry, biotechnology, polymer chemistry, etc., are just some of the many scientific disciplines that study these compounds and their properties.

Frequently Asked Questions

1. Write the order of increasing acidity of hydrohalo acids.

The order of increasing acidity is:

HI>HBr>HCl>HFh

This happens because as the size of the anion increases, its nucleophilicity increases. I– is a strong nucleophile and prefers to stay in such a state. Thus its acidity is highest. 

2. Are all binary compounds conducting in nature?

No, only ionic compounds are conducting in nature. This is because of the formation of free flowing ions which conduct charge. Binary covalent compounds are  not conducting because their atoms are bonded. 

3. Is rust a binary compound?

The chemical formula for rust is FeO. Thus, it is an example of a binary compound since it is only made of two types of atoms. It is an ionic binary compound with iron in +2 oxidation state and it has an octahedral geometry. 

What Are Aldehydes?

Carbon (C) and oxygen (O) form a double bond in aldehyde, making it a carbonyl functional group; carbon (H) and an alkyl group (C=O) form a single bond. As a rule of thumb, aldehyde is denoted as R-CHO. The letter “R” stands for the alkyl group. Carbon (C) is double-bonded to oxygen (O) in all aldehyde chemical compounds, forming the carbonyl group. The prefix “al” is appended to the name of any chemical compound that contains an aldehyde group

What Are Ketones?

A ketone also contains a carbonyl group and is thus a functional group. Here, two alkyl groups (R) are connected by a single bond while the carbonyl carbon (C) is double-bonded to oxygen (O). Ketones are typically written as R-CO-R, where R is an alkyl group. The prefix “one” is added to the name of any compound that contains a ketone group. 

Properties of Ketones 

To put it simply, ketones are liquids at room temperature. Use acetone as an illustration. Ketones have a higher boiling point than aldehydes and alcohols because the carbonyl group they contain exhibits dipolar attraction. The compound’s boiling point rises proportionally with its magnitude. In general, ketones of a lower molecular weight dissolve well in water, but this solubility declines with increasing ketone molecular size.

Properties of Aldehydes

Aldehydes come in a wide range of physical forms. Formaldehyde is one such chemical that, at room temperature, exists in the gaseous state. Formalin is the name given to an aqueous solution of the substance. Most other common aldehydes are liquids at room temperature, however others, depending on the number of alkyl groups, are solids. The lower aldehydes have a strong odour, whereas the higher aldehydes are pleasant, which is why they are used in fragrances. 

Due to the dipolar attraction seen in the polar carbonyl group present in aldehyde, the boiling point of aldehyde is generally high. 

Aldehyde show dissolution in water and other solvents. This is because they have lone pair of electrons in the oxygen (O) of the carbonyl group (C=O) which forms an H- bond with the hydrogen of water. The aldehydes which contain four carbon atoms are generally soluble in water but the solubility of aldehyde in water decreases as the size of the alkyl group increases.

Occurrence Of Ketones And Aldehydes

Many different types of microbes and plants are natural sources of ketones and aldehydes. Examples include cinnamaldehyde from cinnamon bark, citral from lemongrass, vanillin from vanilla bean, carvone from spearmint and caraway, camphor from the camphor tree, and helminthosporal from poisonous fungi, to name a few. Ketones can also be found in animals, such as the muscone found in musk deer, the sex hormones testosterone in males and progesterone in females, and the adrenal hormone cortisone.

Preparation Of Ketones And Aldehydes

Preparation of Aldehyde

Oxidation of primary alcohols: Primary alcohols can be treated with Pyridinium chlorochromate in dichloromethane to form aldehydes.

Dehydrogenation of primary alcohols : Dehydrogenation means the removal of the hydrogen molecule. Primary alcohol undergoes dehydrogenation in the availability of copper forms aldehyde.

From acid chlorides

The reduction of the acid chloride with hydrogen in the availability of palladium catalyst present over barium sulphate with a small quantity of quinoline gives aldehyde. The reaction is said to be Rosenmund’s reaction. 

Preparation from carboxylic acid

When the vapours of carboxylic acid are passed over manganese oxide at 573 K, the aldehyde is produced.  A common example is passing formic through manganese oxide at 573 K to give formaldehyde, carbon dioxide and water.

Preparation from alkenes

Alkenes reacting with ozone in presence of carbon tetrachloride give ozonides which further break down into two molecules of aldehyde in presence of zinc dust and water.

Preparation of ketones

From acid chloride: On reacting with dialkyl cadmium, ketone compound are formed from acid chloride.

Here, acetyl chloride reacting with dimethyl cadmium forms acetone.

From carboxylic acid: When vapours of acetic acid is passed through manganous oxide, acetone is produced.

From alkenes:
2, 3-Dimethylbut-2-ene on ozonolysis gives acetone.

Here, 2, 3-Dimethylbut-2-ene reacting with ozone in presence of carbon tetrachloride gives ozonide which breaks down to acetone.

From akynes:

Propyne reacting with a hydrated mixture of dilute sulphuric acid and mercuric sulphate gives acetaldehyde.

Uses Of Aldehydes And Ketones

Perfumes typically include organic compounds containing aldehyde, such as vanilla, orange rind, rose, and citronella. Because of their pleasant aroma, these chemicals are synthesised in laboratories and used in the creation of perfumes and colognes. Because of its signature scent, benzaldehyde is also a popular ingredient in fragrances.

Aldehydes have several industrial applications, including in the production of chemical compounds, dyes, and resins. Because of its effectiveness as a preservative for biological specimens and its antimicrobial qualities, formaldehyde is often manufactured industrially on a larger scale. The most widely utilised ketone molecule, acetone is primarily employed as a solvent in the production of chemicals like iodoform and iodoform. The nail polish remover contains it.

Formation by Oxidation of Alcohols

Aldehyde: Primary alcohol oxidises of aldehyde in presence of acidified potassium dichromate (\({{\bf{K}}_2}{\bf{C}}{{\bf{r}}_2}{{\bf{O}}_7}\)) or alkaline potassium permanganate (\({\bf{KMn}}{{\bf{o}}_4}\)).

Here, ethyl alcohol oxidises to acetaldehyde.

Ketone: Secondary alcohol on oxidation in presence of acidified potassium dichromate (\({{\bf{K}}_2}{\bf{C}}{{\bf{r}}_2}{{\bf{O}}_7}\)) or alkaline potassium permanganate (\({\bf{KMn}}{{\bf{o}}_4}\)) gives ketone.

Here, isopropyl alcohol is oxidised to acetone.

Formation by Alcohols Dehydrogenation

Aldehyde: Primary alcohol undergoes dehydrogenation in the availability of copper forms aldehyde.

Ethyl alcohol on heating with copper changes to acetaldehyde and hydrogen molecule is removed.

Ketone: Heating of secondary alcohol in presence of reduced Cu at 573 K forms ketone.

Summary

Carbonyl-containing organic substances include aldehydes and ketones. Aldehyde and ketones can be synthesised industrially on a massive scale in addition to being derived naturally from plants and bacteria. Its versatility in application has led to their widespread use. Both chloroform and iodoform require acetone as an input in their production. Dye manufacturing (like malachite green) and chemical synthesis (such benzoic acid and benzoyl chloride) all rely on benzaldehyde. There are a variety of additional organic molecules that can be used as building blocks for making aldehyde and ketones, respectively.

Frequently Asked Questions

1. Which test is common for the detection of both aldehyde and ketone groups?

Ans: Both aldehyde and ketone groups give 2, 4-Dinitrophenylhydrazine. When 2,4-DNP or Brady’s reagent is reacted with pure carbonyls, it forms precipitate which is yellow-orange in colour. 

2. What is a Schiff Base?

Ans: A Schiff base is a compound with the general structure R2C=NR’ and is considered as a subclass of imines. Schiff’s test is a chemical test used to check for the presence of aldehydes in a given analyte. 

3. Out of aldehydes and ketones which one is more reactive and why?

Ans: Aldehydes are more reactive towards nucleophilic addition reactions. Since the carbonyl group of ketones is connected to alkyl groups, and the alkyl group has electron donating inductive effect, it increases electron density on carbon of carbonyl group in ketones, making it less electrophilic.

What are Aldehydes?

Carbon in an aldehyde forms double bonds to oxygen and single bonds to hydrogen and an alkyl group, making it a carbonyl functional group.  The letter “R” stands for the alkyl group. Known as the carbonyl group, aldehyde chemical compounds all have a carbon atom double-bonded to oxygen. An aldehyde group’s carbon atom can come from any unsaturated, saturated, or cyclic carbon chain. A carbon atom in an aldehydic molecule will have at least one hydrogen atom attached to it.

Naturally Occurring Aldehydes

Naturally occurring aldehyde compounds are widespread in flora and fauna. Vanillin can be found in vanilla beans and cinnamaldehyde in cinnamon bark. Citral is extracted from lemongrass. 

General Properties Of Aldehydes

Physical State: Aldehydes come in a wide range of physical forms. Formaldehyde is one such chemical that, at room temperature, exists in the gaseous state. Formalin is the name given to an aqueous solution of the substance. Most other common aldehydes are liquids at room temperature, however others, depending on the number of alkyl groups, are solids. The lower aldehydes have a strong odour, whereas the higher aldehydes are pleasant, which is why they are used in fragrances.

Boiling Points:  Due to the dipolar attraction seen in the polar carbonyl group present in aldehyde, the boiling point of aldehyde is generally high. 

Solubility:  Water and other solvents are effective at dissolving aldehyde. The oxygen (O) in the C=O molecule has a lone pair of electrons, so it can form a H bond with the hydrogen in water. In general, aldehydes with four carbon atoms are soluble in water, although the solubility diminishes with increasing alkyl group size.

Uses Of Aldehydes

• Organic compounds like vanilla, orange rind, rose and citronella contain aldehyde. These compounds are created synthetically in laboratories and utilised for the production of perfumes and colognes due to their sweet smell.
• Aldehydes are used for making different organic compounds, dyes, and resins. Formaldehyde is prepared industrially on a larger scale and is used as a preservative for biological specimens and also has antibacterial properties.

Preparation of Aldehydes

There are many preparative methods for aldehydes. A few of them are discussed below.

Oxidation of primary alcohols: Primary alcohols can be treated with Pyridinium chlorochromate in dichloromethane to form aldehydes.

Dehydrogenation of primary alcohols : Dehydrogenation means the removal of the hydrogen molecule. Primary alcohol undergoes dehydrogenation in the availability of copper forms aldehyde.

From acid chlorides

The reduction of the acid chloride with hydrogen in the availability of palladium catalyst present over barium sulphate with a small quantity of quinoline gives aldehyde. The reaction is said as Rosenmund’s reaction. 

Preparation from carboxylic acid

When the vapours of carboxylic acid are passed over manganese oxide at 573 K, the aldehyde is produced.  A common example is passing formic through manganese oxide at 573 K to give formaldehyde, carbon dioxide and water.

Preparation from alkenes

Alkenes reacting with ozone in presence of carbon tetrachloride give ozonides which further break down into two molecules of aldehyde in presence of zinc dust and water.

Nomenclature of Aldehydes

Aldehydes can be identified with the suffix -al, in other words, any hydrocarbon name that ends with the suffix -al is referred to as aldehyde. For example methanal, ethanal, and propanal. The nomenclature of aldehyde is done using the IUPAC naming system. IUPAC stands for International union of pure and applied chemistry. 

1. First, the numbering of carbon atoms starts from the carbonyl carbon. Here, the number of total carbon (C) atoms is three so the hydrocarbon chain is “propane” and the root word is “propan”.
2. As the aldehyde group is present (-CHO) the “ane” suffix is changed by “al” forming propanal.
3. So, the IUPAC name of the given compound is propanal.

Structure of Aldehydes

The general structure of aldehyde is shown below.

 Aldehyde

Here, the carbonyl carbon is \(s{p^{2}}\) hybridised. The chemical compounds containing carbonyl groups like aldehyde and ketone have planar geometry. The bond angle is 120 degrees. In the carbonyl group, the oxygen atom is more electronegative in nature than carbon which indicates that it is a polar group. As a result, the dipole moment is 2.3 D to 2.8 D.

Tests for Aldehydes

2, 4-DNP Test: Here, the organic compound is mixed with an acidic solution of 2, 4-dinitrophenylhydrazine along with methanol. After some time, a formation of a red precipitate is observed. The red precipitate is of 2,4-dinitrophenylhydrazone. The solid crystals are filtered and by recrystallisation method, solid mass is obtained. The hydrazone derivative has a distinct melting and boiling point which helps to detect the carbonyl group. Further, as the presence of the carbonyl group is detected, we can also find out whether the compound is ketone or aldehyde.

As the precipitate obtained is in solid form, it can be filtered out and the melting point of the solid can be determined. By comparing the melting point of the precipitate to the known value of ketone and aldehyde, the carbonyl group present in the compound can be detected.

Schiff’s reagent: It is a pink colour dye which gets decolourised by passing sulphur dioxide gas. When aldehyde is treated with Schiff’s reagent, the colour is retained.

Summary

Aldehyde is one of the classes of functional groups containing a carbonyl carbon attached to oxygen by a double bond and to an alkyl group and hydrogen by a single bond. The aldehyde can be identified by the suffix “al”. The general formula of aldehyde is R-CHO. Higher grade aldehydes are used for the preparation of perfumes and colouring agents due to their sweet smell. The aldehyde can also be synthesised by different methods as discussed. A few examples of aldehydes are formaldehyde, Ethanal, Propanal, Butanal etc. Some naturally occurring aldehydes are vanillin, citral, etc.

Frequently Asked Questions

1. Why are aromatic aldehydes less reactive than aliphatic aldehydes?

Ans: Aromatic aldehydes are less reactive because the lone pair of oxygen atoms is involved in resonance with the benzene molecule. This makes the carbonyl group less nucleophilic. 

2. Which reducing agent is used for aldehydes?

Ans: Sodium Borohydride is also called as tetra hydrido borate is used as a reducing agent of aldehydes. The aldehydes are converted into primary alcohols. 

3. Which type of aldehyde compound can undergo aldol condensation?

Ans: The aldehyde compound containing alpha hydrogen undergo aldol condensation. This is because only compounds with alpha hydrogen can form beta-hydroxy aldehydes, which is the end product of the reaction. 

Introduction

The -OH bond is present in the functional group of alcohols and phenols. Carbonyl compounds are another type of organic chemical that contain the C=O group. More than one class of chemical compounds has this cluster. Carbonyl compounds, which include aldehydes and ketones, are a class of organic molecules distinguished by the presence of a carbonyl group (>C=O). The group is attached to a Hydrogen atom in aldehydes. Lack of hydrogen allows the carbonyl group to be referred to as the ketonic group; this group is absent in ketones.

Whereas aromatic ketones have no alkyl groups, aliphatic ketones have from one to three. An aryl group must be present in at least one of them. Both families share a carbonyl group, which explains why their members are so similar in appearance and how they are prepared. Nevertheless, aldehydes and ketones have different reactivities because of the presence of a hydrogen atom in aldehydes against the absence of such an atom in ketones. Aldehydes and ketones are similar in that they are both highly reactive. Because of the carbonyl group’s reactivity as a polar, Pi ()-bonded carbonyl radical.

What are Alcohols?

For alcohols and phenols to develop, one or more hydrogen atoms must be exchanged from the original hydrocarbon. In regards to alcohols, the -OH is the hydroxyl group. A phenolic group resides in or is conjugated to a benzene ring. The alcohols do not allow for any search resonance. That’s why phenols are so acidic, whereas alcohols are so basic. Monohydric alcohols, or -OH alcohols, only have one hydroxyl (-OH) group.

In chemical notation, these are written as R-OH. Based on the characteristics of the carbon atoms with which the -OH group forms a bond, these are further classified as primary (1°), secondary (2°), or tertiary (3°) hydroxyl groups.

Oxidation of Alcohols to Aldehydes and Ketones

Method of Preparation of Aldehydes 

Aldehydes are the oxidation products of primary alcohols. The oxidation is normally carried with acidified \({{\bf{K}}_2}{\bf{C}}{{\bf{r}}_2}{{\bf{O}}_7}\) or aqueous/alkaline \({\bf{KMn}}{{\bf{o}}_4}\).

When Ethyl alcohol is reacted with alkaline \({{\bf{K}}_2}{\bf{C}}{{\bf{r}}_2}{{\bf{O}}_7}\) it immediately oxidised to Acetaldehyde and gives water.

\({\bf{C}}{{\bf{H}}_3}{\bf{C}}{{\bf{H}}_2}{\bf{OH}} + {\rm{ }}{\bf{KMn}}{{\bf{O}}_4} \to {\bf{C}}{{\bf{H}}_3}{\bf{CHO}}{\rm{ }} + {{\bf{H}}_2}{\bf{O}}\)

In case alcohols, particularly aromatic, have poor solubility in water, then a solution of chromic acid (\({{\bf{H}}_2}{\bf{Cr}}{{\bf{O}}_4}\))  dissolved in acetone (\({{\bf{C}}_3}{{\bf{H}}_6}{\bf{O}}\)) can be used. This is known as Jones reagent.

\({{\bf{C}}_6}{{\bf{H}}_5} – {\bf{C}}{{\bf{H}}_2}{\bf{OH}}{\rm{ }} + {{\bf{H}}_2}{\bf{Cr}}{{\bf{O}}_4} + {{\bf{C}}_3}{{\bf{H}}_6}{\bf{O}} \to {{\bf{C}}_6}{{\bf{H}}_5} – {\bf{CHO}}{\rm{ }} + {\rm{ }}{\bf{Water}}\)

Method of Preparation of Ketones

Ketones are products of oxidation of secondary alcohols. The oxidation is normally carried with acidified \({{\bf{K}}_2}{\bf{C}}{{\bf{r}}_2}{{\bf{O}}_7}\) or aqueous/alkaline \(\;{\bf{KMn}}{{\bf{o}}_4}\).

\({{\bf{C}}_2}{{\bf{H}}_6}{\bf{CHOH}} + {\rm{ }}{\bf{KMn}}{{\bf{O}}_4} \to {{\bf{C}}_2}{{\bf{H}}_6}{\bf{C}} = {\bf{O}}{\rm{ }} + {{\bf{H}}_2}{\bf{O}}\)

Oxidation of secondary alcohols can also be done with the help of oppenaur oxidation in which the secretarial course is refluxed with excess acetone in the presence of aluminium tertiary butoxide in benzene or toluene solution. The secondary alcohol is oxidised to corresponding ketone while ketones simultaneously reduce to secondary alcohol.

Reduction of Alcohols

• Alkyl halides are best prepared from alcohols by replacing the group with halogen atom ().
• Alkyl chlorides or chloroalkanes are prepared by reacting in alcohol with a mixture of anhydrous and Hydrogen Chloride gas (mixture is called Lucas reagent). This is known as Groove’s process.

\({\bf{C}}{{\bf{H}}_3}{\bf{C}}{{\bf{H}}_2}{\bf{OH}}{\rm{ }} + {\rm{ }}{\bf{HCl}}\left( {\bf{g}} \right){\rm{ }} + {\rm{ }}{\bf{Anhy}}{\rm{ }}{\bf{ZnC}}{{\bf{l}}_2} \to {\bf{C}}{{\bf{H}}_3}{\bf{C}}{{\bf{H}}_2}{\bf{Cl}}{\rm{ }} + {{\bf{H}}_2}{\bf{O}}\)

Identification Tests of Alcohols

Special tests are employed to detect alcohols and to determine their specific nature. These are described as follows.

Vector Meyer’s Test (Red blue Colourless Test)

The given alcohols are first converted to the alkyl iodide by reacting \(p/{I_2}\left( {p{I_3}} \right)\)The alkyl iodide is converted to the corresponding Nitro derivative with silver nitrite (\(AgN{O_2}\)). The Nitro derivative is then reacted with nitrous acid(\(NaN{O_2} + HCl\)) and the resulting solution is made alkaline.

• A blood red colouration indicates primary alcohol.
• A blue colouration indicates secondary alcohol
• A colourless solution represents tertiary alcohol

Lucas Reagent Test

This test is based on the reactivities of primary secondary and tertiary alcohols with Hydrochloric acid. The given alcohols are treated with Lucas reagent, which is an equal mixture of concentrated  and anhydrous \(ZnC{l_2}\) which is a dehydrating agent. The product is alkyl chloride or chloroalkane followed by white, turbidity or cloudiness.

\({\bf{Primary}},{\rm{ }}{\bf{Secondary}},{\rm{ }}{\bf{Tertiary}}{\rm{ }}{\bf{Alcohol}}{\rm{ }} + {\rm{ }}{\bf{HCl}}{\rm{ }} + {\rm{ }}{\bf{Anhy}}{\rm{ }}{\bf{ZnC}}{{\bf{l}}_2} \to {\bf{Alkyl}}{\rm{ }}{\bf{Chloride}}{\rm{ }} + {{\bf{H}}_2}{\bf{O}}\)

The time taken for the appearance of turbidity is different in the 3 types of alcohols and affords a method for their distinction.

1. If the turbidity appears immediately, alcohol is tertiary
2. If the turbidity appears after sometime, alcohol is secondary
3. In case the turbidity appears on heating, alcohol is primary

Summary

The alcohol and phenol functional groups both feature a -oH bond. Carbonyl compounds are another type of organic chemical that contain the >C=O group. More than one class of chemical compounds has this cluster. Carbonyl compounds, which include aldehydes and ketones, are a class of organic molecules distinguished by the presence of a carbonyl group (>C=O). The group is attached to a Hydrogen atom in aldehydes. There is no hydrogen atom in ketones, and the carbonyl group is sometimes referred to as the ketonic group.

 

Frequently Asked Questions

1. What are the environmental impacts of the oxidation of alcohols?

Ans: Oxidation of alcohols makes heavy use of water resources. It needs resources like land and water in order to flourish. It occurs in high energy consumption factories. Creates waste that ends up in landfills because of packaging.

2. What is the role of a catalyst in the oxidation of alcohols?

Ans: Catalytic oxidation of alcohols is an essential process for energy conversion, production of fine chemicals and pharmaceutical intermediates. It makes the process quick and increases yield.

3. Why we are unable to get aldehyde on reaction between primary alcohols and \({{\bf{K}}_2}{\bf{C}}{{\bf{r}}_2}{{\bf{O}}_7}\) ?

Ans: \({{\bf{K}}_2}{\bf{C}}{{\bf{r}}_2}{{\bf{O}}_7}\)  cannot be used to oxidize primary alcohols to aldehydes. The oxidation will not stop at aldehyde stage. It will further continue to carboxylic acid.

Introduction

Alcohols and phenols are formed by replacing one old hydrogen atom in the hydrocarbon. In the case of alcohols, the -OH is known as the hydroxyl group, while it is called the phenolic group. It is attached to a benzene ring. Since they have a common functional group, most of the characteristics of alcohols and phenols are expected to be the same. However, they do differ in many properties. It is primarily due to the reason that the phenolic group is involved in residence or conjugation with the benzene ring. While no search resonance is possible in alcohols. This makes phenols considerably acidic while alcohols hardly exhibit any acidic in nature. Members of both these families have analytical and industrial importance.

Structure of Alcohol

Alcohols which contain one -OH group that is monohydric compounds are also known as alcohols. These are represented by the formula R-OH These are additionally categorised as primary (1°), secondary (2°) and tertiary (3°) varying on the behaviour of the carbon atoms to which the -OH  group is bonded. For example,

Structure of Phenol

Phenols are aromatic compounds that contain one or more, -OH groups called phenolic groups that are attached directly to the ring. Phenols may be further classified as monohydric, dihydric, trihydric, etc, depending upon the number of -OH, groups bonded to the ring.

Monohydric phenols known as the parent or simplest member of the family with one -OH group attached to the ring are called phenol.

In dihydric phenolic compounds 2 -OH, groups are attached directly to the ring.

Trihydric phenols compounds are known in which 3 -OH groups are directly attached to the ring

Difference Between Hydroxyl and Alcohol

What is Hydroxyl?

The term hydroxyl is used to refer to the -OH radical. A functional group found in both organic and inorganic compounds is the hydroxyl group. The chemical formula for this compound is -OH. As a result, the hydroxyl group is made up of one hydrogen and one oxygen atom. The hydroxyl radical is extremely reactive and can initiate chemical reactions almost instantly. The Hydroxyl radical is the Hydroxide ion’s neutral form OH–. This hydroxyl radical has an unpaired electron, which results in the radical’s high reactivity.

What is the Relationship Between Hydroxyl and Alcohol?

Alcohols are composed of the  -OH  groups. These -OH groups behave as the functional group of alcohols. Consequently, the -OH group affects the physical and chemical properties of alcohols.

Because of -OH group presence alcohols tend to show some properties that are only because of the -OH group.

1. They are polar compounds directly because of the presence of -OH groups.
2. Alcohols are soluble in polar solvents.
3. Alcohols have the ability to form Hydrogen bonds.
4. Alcohols are soluble in water.
5. Alcohols tend to have higher boiling points than the equivalent alkanes because of the existence of these hydrogen bonds.

Summary

Alcohols and phenols are formed by replacing one or more hydrogen atoms in hydrocarbons by -OH groups. In the case of alcohols, the -OH group is known as the hydroxyl group, while it is called the Phenolic group when connected to a benzene ring. Given that they have the same functional group, most of the properties of alcohols and phenols are believed to be similar. Nevertheless, they do not differ in many properties, it is mainly because of the explanation that the phenolic group is engaged in resonance or conjugation with the benzene ring. However, no such resonance is feasible in alcohols. This makes phenols significantly acidic, while alcohols barely demonstrate any acidic character. Members of both these families have analytical and industrial significance. Ethyl alcohol, commonly called alcohol, is a starting material for the manufacture of ether, chloroform, acetic acid, etc. It can also be used as a fuel for spirit lamps and stoves due to its highly combustible nature. But it’s important, is in its ability to act as a beverage in the form of beer, wine, whisky, Brandy, etc. phenol finds application in the synthesis of Bakelite, plastics, drugs, etc.

Frequently Asked Questions

1. Out of Phenols and Alcohols, which one is more acidic in nature and why?

Phenols are more acidic in nature because of the explanation that the phenolic group is engaged in resonance or conjugation with the benzene ring. However, no such resonance is feasible in alcohols. This makes phenols significantly acidic, while alcohols barely demonstrate any acidic character.

2. Name the tests to distinguish between primary, secondary and tertiary  

    Alcohol?

In the chemical properties of alcohols, we have seen that the three types of alcohols differ in the nature of their products. However, they cannot be distinguished practically based on these characteristics. Special tests are employed for this purpose. These are described as follows.

Victor Meyer’s Test (Red-blue Colourless Test)

1. In this, a blood-red colouration indicates primary alcohol.
2. A blue colouration indicates secondary alcohol
3. A colourless solution represents tertiary alcohol

Lucas Reagent Test

1. If turbidity appears immediately, alcohol is tertiary
2. If turbidity appears after some time, alcohol is secondary
3. In case turbidity appears on heating, alcohol is primary

3. Describe Lucas Reagent test? Why is it important? What are its limitations?

This test is based on the reactivities of primary secondary and tertiary alcohols with Hydrochloric acid. The given alcohols are treated with Lucas reagent, which is an equal mixture of concentrated HCl and anhydrous \(ZnC{l_2}\), which is a dehydrating agent. The product is alkyl chloride or chloroalkane accompanied by white, turbidity or cloudiness.

The time taken for the appearance of turbidity is different in the 3 types of alcohols and affords a method for their distinction.

1. If the turbidity appears immediately, alcohol is tertiary
2. If the turbidity appears after sometime, alcohol is secondary
3. In case the turbidity appears on heating, alcohol is primary

Limitations of Lucas reagent.

Lucas reagent test is not applicable to the alcohols with 6 or more carbon atoms. As they are not water soluble, no reaction with Lucas reagent is possible.

4. Describe the physical properties of Phenols?

• State and smell. Phenols are either colourless crystalline solids or liquids. However, when exposed to the atmosphere, they become reddish or pinkish due to the formation of oxidation products. Phenols have a characteristic smell, known as phenolic smell. 
• Solubility. I like alcohol. Phenols are only sparingly soluble in water. They are also expected to form hydrogen bonding with water molecules due to the polar nature of the -OH group present. 
• Boiling points. Phenols are expected to have higher boiling points than expected from their molecule formula, mainly because of the polar nature of the -OH group. Thus, these are having higher boiling points than the aromatic hydrocarbons of comparable molecular masses. 

5. What will happen when alcohol is oxidised?

Oxidation of primary alcohols to aldehyde

Aldehydes are the oxidation products of primary alcohols.

Oxidation of secondary alcohols to Ketones

Ketones are products of oxidation of secondary alcohols.