Tag: Molecules

Introduction

There is matter in our universe. The matter is anything that maintains a quantity and a space. These things have a fundamental unit that cannot be divided into other parts with various chemical and physical properties. An atom is this fundamental component. An element is a substance that only contains one type of atom. Therefore, the species made up of a specific atom are the elements. For instance, there is only one type of atom in pure platinum metal. The atom was once thought of as an indivisible unit, but now it can be divided, releasing a huge amount of energy in the process.

Define an Atom and Molecule

An atom is the tiniest component of matter. The physical and chemical characteristics of the atoms that make up an element are all the same type. An atom is mono-nuclear, meaning that it has just one nucleus, which is surrounded by electrons and houses protons inside the central mass of the atom, the nucleus.

Chemical bonds bind the minimum required number of atoms in a molecule together. It is the joining of various atoms with the assistance of a chemical bond. The molecule oxygen\(\;({O_2})\) is a diatomic homo nuclear structure made up of two oxygen atoms bound together by a covalent bond.

What is the size of an Atom?

Only an estimation of an atom’s size can be made because it is impossible to measure it precisely. However, an atom’s atomic radius determines its size. Atomic radius is calculated by dividing the distance between adjacent atoms in a compound by two. Radii come in a variety of forms, including metallic, covalent, and ionic radii. The metallic radius is the separation between adjacent atoms in a metal. The covalent radius is the separation between adjacent atoms in a covalent compound. Ionic radii are the distances between adjacent ions in an ionic compound.

How atoms are formed?

The atom is the smallest unit of matter, consisting of a nucleus and electrons. The nucleus is the central portion of the atom that contains the positively charged proton and neutral neutron. And is surrounded by electrons that are negatively charged. Protons, electrons, and neutrons make up an atom. They are collectively known as subatomic particles.

Forces between Atom and a Molecule

Molecules are formed when atoms are held together by a strong chemical bond. These bonds are formed by the interaction of an element’s valence electrons to complete the octet. Chemical bonds are classified into several types. They do,

1.Ionic bond: When two atoms approach each other and have a large electronegativity difference, electrons, and anion forms are accepted. And the one that lost an electron will become an anion. An Ionic bond is formed as a result of the attraction caused by the positive and negative charge.

2.Covalent bond: When atoms with similar electronegativity differences approach each other, they share electrons. And this is a covalent bond.

Summary

Chemistry’s fundamental terms are atoms and molecules. Atoms are the fundamental building blocks of elements. A molecule is formed by the combination of different atoms using a chemical bond. These bonds could be covalent or ionic. Protons, neutrons, and electrons make up an atom. The size of an atom cannot be calculated precisely; only an approximation of size is possible. 

Frequently Asked Questions 

1. What exactly are isotopes?

Ans. Isotopes are atoms with the same atomic number but different mass numbers. The same atomic number denotes the same number of protons. And a different mass number means a different neutron number.

2. What is the mass number?

Ans. The mass number is the sum of protons and neutrons added to an atom of a chemical element. Lithium, for example, has a mass number of 7. Lithium has 3 protons and 4 neutrons.

3. What is the chemical formula?

Ans. A molecular formula is an expression used to represent a chemical compound that is the simplest whole-number ratio of the composition of elements present in a molecule.

An Introduction to Matter

In addition to taking on various forms, the matter is composed of small particles. Because they are so small, it is impossible to see these particles with the human eye. We have mentioned below some of the various properties of matter. There are different states of matter can also be found. The three common states are solids, liquids, and gases. Atoms and other particles with mass and volume are included in the matter.

What do you understand by the Characteristics of Particles of Matter?

We are aware that every substance in our environment is composed of small matter particles. This means that these particles have some attributes and can affect the status of properties. These characteristics of the substance can be either physical or chemical.

For more help, you can Refer to our video in Science Concept. Check out the video Lesson for a better understanding.

What are the Characteristics of Particles of Matter

The particles of matter are very, very small.

1. The particles of matter have space between them.
2. The particles of matter are constantly moving.
3. The particles of matter attract each other.

Let’s try to explain each characteristic of particles of matter with the help of an experiment.

The particles of matter are very, very small

You can demonstrate the extremely small size of matter particles by carrying out the following experiment with water and potassium permanganate.

1. Put two or three crystals of potassium permanganate in a beaker with 100 ml of water, and mix. The potassium permanganate solution in water will be a dark purple tint.
2. Approximately 10 ml of this solution should be taken out and placed in the second beaker with 90 ml of pure water. The second beaker’s potassium permanganate solution’s colour lightens slightly as a result of this dilution.
3. Take 10 ml of this mixture and add it to the third beaker’s 90 ml of clear water. The solution’s colour will continue to lighten.
4. Continue dilution of the solution in this manner 5–8 times.
5. We obtain a potassium permanganate solution in water in this manner, but the water is still coloured.
6. This experiment demonstrates how a small amount of potassium permanganate crystals may colour a significant amount of water.
7. Therefore, conclude that each potassium permanganate crystal must contain millions of minuscule particles that continually divide into smaller and smaller particles.

The particles of matter have space between them

The experiment below, which uses water and sugar, can be used to demonstrate the gaps between the particles of matter.

1. Have a 100 ml beaker ready.
2. Mark the water level after adding half of the water to the beaker.
3. Utilizing a glass rod, dissolve 50g of sugar.
4. We’ll discover that the sugar solution’s level in the beaker is exactly where the water level was when the beaker was first filled.
5. The crystals of sugar break down into incredibly small particles when they are dissolved in water. Since these sugar particles occupy the spaces between the different water particles, adding sugar to water does not change its volume.
6. When sugar is dissolved in water, there is no change in volume, which indicates that there are voids between the water molecules.

The particles of matter are constantly moving

The investigations on diffusion and Brownian motion gave the particles their characteristic of continual motion. 

1. Water and red ink slowly combine, causing the water to eventually turn crimson. 
2. The movement of matter particles is demonstrated by this action.

The particles of matter attract each other

The forces of attraction that hold matter particles together are known as gravitational forces. Cohesion is the term denoting the force of attraction between particles of the same substance.

1. When a piece of chalk, a cube of ice, and an iron nail are all hit with a hammer, the chalk is very easily broken into smaller pieces while the ice cube requires more energy to break, and the iron nail remains intact even when hit with a lot of force.
2. This demonstrates that the force of attraction between the chalk particles is very weak, the force between the ice particles is a little stronger, and the force between the iron nail particles is quite strong.

Summary

There are three different types of physical nature in the world around us. Solid, liquid, and gas are these we breathe in air, which is a gas, and we drink water, which is a liquid. Because different types of matter contain varied amounts of inter-particle space, we have mentioned three possible states of matter. In this article, we studied the characteristics of solids, liquids, and gases. In a nutshell, this is how matter behaves physically in the universe.

Frequently Asked Questions

Question 1. What are the several forms that matter can take?

Solids, liquids, and gases are the three states in which matter can be found. Ice is a solid, water is a liquid, and steam is water in a gaseous state. Therefore, matter exists in all three states.

Question 2. How can you ascertain the material’s physical characteristics?

We are aware that everything we see is made of something. They take up space and have mass. It’s crucial to realise that not all matter has the same physical characteristics. One common illustration of this fact is the fact that while sand particles are insoluble in water, salt particles are. Therefore, these elements can be referred to as matter’s physical characteristics.

Question 3. What is Diffusion?

In matter, particles are constantly in motion. Diffusion is the term used to describe the natural mixing of particles from two different materials. The diffusion of these particles inside the substance speeds up as the temperature rises. It gets faster because as the temperature rises, the kinetic energy of the particles rises as well. They move quickly as a result.

An introduction to Molecules

Atoms are the building blocks of all living things on this planet. An atom is the smallest unit that makes up a chemical element. Atoms make up everything else that is solid, liquid, or gas. Atoms are made up of protons, neutrons, and electrons that are contained within the nucleus of an atom. What happens when two or more atoms collide? They combine to form molecules. Molecules are formed when two or more atoms form chemical bonds with one another. Understanding the properties and structure of atoms and molecules is not easy, but once understood, it is a fascinating subject to study.

What are Molecules?

Elements are created when the same types of atoms combine. The number of atoms that make up a molecule has the same ratio. The structure of elements determines their properties. Elements can be made up of one or more atoms. Take, for example, oxygen, which has two atoms (\({O_2}\)). Atoms are not depicted to scale. A compound is formed when these elements are combined. We can use \({H_2}O\) in this case. Water contains two hydrogen atoms and one oxygen atom. Similarly, larger chemical compounds such as methane (\(C{H_4}\)). We can learn from these how a group of atoms with a nucleus can form elements and compounds with various properties and structures.

What is the difference between Atoms and Molecules?

Atoms	Molecules
Atoms are the smallest particle that can exist.	Two or more atoms combined to form molecules.
Atoms may not be stable due to the presence of electrons in the outer shells.	Molecules attain stability.
They contain protons, neutrons, and electrons.	Two or more atoms are formed and hence, they are strong.
Examples: Oxygen (O), phosphorus (P), sulphur (S) etc.	Examples: Oxygen (O2), water (H2O), and sulphur (S8).

Summary

Elements can be single atoms, such as He, or elemental molecules, such as hydrogen (\({H_2}\)), oxygen (\({O_2}\)), chlorine (\(C{l_2}\)), ozone (\({O_3}\)), and sulphur (\({S_8}\)). Atoms are not depicted to scale. Some elements are monatomic, which means that their molecular form is made up of a single (mono-) atom (-atomic).

Frequently Asked Questions (FAQs)

1. What do you understand by the Law of Conservation of Mass?

Ans: According to this law, “Mass can neither be created nor destroyed.” This law can be applied to a chemical reaction in the following way:- During a chemical reaction, the total mass of reactants equals the total mass of products.

\[\left( {Reactant} \right){\rm{ }}A + B{\rm{ }} \to {\rm{ }}AB{\rm{ }}\left( {Product} \right)\]

2. What is an atom?

Ans. According to modern atomic theory, an atom is the smallest particle of an element that participates in a chemical reaction and retains its identity throughout the chemical or physical change.

3. What do you understand by the Law of Constant Proportion?

Ans. According to this law, “A pure chemical compound always contains the same elements combined in the same proportion by mass, irrespective of the fact from where the sample has been taken or from which procedure has it been produced.”

Introduction

Pressure can be defined as the force exerted perpendicularly per square unit of area of any object. It is represented by the formula,                                                                                                                        

                                                             P = F ⁄ A

where P is the pressure, F is the force exerted on the object, and A is the area of the object. Pressure is measured in pascal, and is classified into absolute, atmospheric, differential, and gauge pressure. A change in pressure has different effects on different states of matter.

Change in Pressure

Since the pressure exerted on an object is the amount of force applied per unit area of that object, a change in area or a change in the amount of exerted force can result in a change in pressure. For example, if the surface area decreases, the pressure increases simultaneously when the surface area decreases, the pressure decreases provided that the force applied remains constant. 

Effect of Pressure on the States of Matter

Pressure change can have different effects on different states of matter. By exerting pressure on the matter particles, we can draw them closer. Therefore, applying pressure can cause liquids to turn into solids, and when pressure is applied to a gas that is contained in a cylinder, the gas begins to compress and turn into a liquid. As pressure rises, the volume of the gas reduces, which causes the gas to change into a liquid and then finally a solid. The volume of a gas is inversely related to its pressure and directly relates to the number of molecules it contains.

Pressure has less of an impact on solids because they are non-compressible forms of matter. By applying pressure and lowering the temperature, liquids can be transformed into solids.

Effect of Pressure on Equilibrium

The equilibrium will adjust to minimize a change in the pressure of a gaseous reaction mixture. If the pressure is raised, the equilibrium will change to favour a fall in the pressure. The equilibrium will change if the pressure is reduced to favour an increase.

When a system’s volume is reduced, the pressure will rise (and the temperature is constant). A greater number of collisions occur with the container’s walls. There will be fewer collisions and hence less pressure if there are fewer gas molecules. The equilibrium will change in a way that reduces the number of gas molecules, which will likewise reduce the pressure. To forecast which way equilibrium will shift in response to a change in pressure, we must consider how many gas molecules are involved in the balanced reactions.

For example, the chemical reaction between nitrogen and hydrogen is shown below:

                                                           N2 (g) + 3H2 (g)→ 2NH3↑

The proportion in the equation that balances is 1:3:2. In other words, the 1N2 molecule combines with the 3H2 molecule to produce NH3 gas (from the balanced equation). Four molecules of reactant gas must therefore be present to produce two molecules of product gas.

• Pressure buildup will favour the reaction which results in fewer gas molecules. Because there are fewer product gas’ molecules, the forward reaction is more advantageous. Due to the rightward shift in equilibrium, the yield of NH3 will rise.
• The reaction that produces more gas molecules will be more favourable as pressure drops. If there are more reactant gas molecules present, the reverse reaction is more favourable. As a result of the equilibrium shifting to the left, the yield of NH3 will decline.

Some Facts

• Pressure is directly proportional to the temperature.
• In contrast to solids and liquids, gases are more easily subjected to pressure.
• Compared to gases, solids and liquids are less sensitive to pressure.
• When air pressure is raised, the boiling point of water rises.
• The equilibrium will adjust to minimize the change in pressure of the gaseous mixture.

Frequently Asked Questions

1. Does Changing the Size of the Container Affect the Pressure?

Ans: No change in concentration could change the pressure if the equilibrium reaction does not involve a change in the number of molecules in the gas phase. Therefore, altering the container’s size without also altering the pressure would have no impact on the reaction. The number of molecules stays constant and applies the same pressure whether the container size decreases or grows.

2. How can the Physical Condition of the Matter be Altered?

Ans: It is also possible to change the physical state of matter by adjusting the pressure that is applied. For example, by applying pressure and lowering the temperature, gases can liquefy. 

3. How does Pressure Affect the Boiling Point of a Liquid?

Ans: All liquids evaporate with an expansion. The expansion and delay of vaporization are the results of pressure on the surface. As a result, when pressure is applied, the boiling point rises.