Structure of matter : Solids, Liquids and Gases

Key Concepts

1. Solids
2. Liquids
3. Gases
4. Force
5. Motion

Introduction: Solids, Liquids and Gases

We know that atoms are very small particles that make all the matter. It is the basic particle for all the matter. Atom is the basic unit, and in turn, it is composed of three major particles called electrons, protons, and neutrons. The protons and neutrons combined are at the centre of the atom and are called a nucleus, whereas the electrons revolve around the nucleus. 

Atom and its components: 

The atom is the primary unit of matter. It is composed of electrons, protons, and neutrons. 

Neutrons:  

Neutrons are the neutrally charged particles in the atom. They are at the centre of the atom. 

Protons:  

Protons are the positively charged particles in the atom. They are located at the centre of the atom with the nucleus. The centre of the atom contains neutrons and protons and it is called a nucleus. 

Electron:  

Electron is the negatively charged particle in the atom. The electrons revolve around the nucleus. 

Plasma:  

Plasma is similar to that of the gaseous state and usually occurs at high temperatures only. The plasma is made of atoms and 

Particles in Matter: 

Any object has a collection of atoms in it. Even if the object is at rest, the tiny particles in the atom keep on moving. We cannot observe it through our naked eyes as it is microscopic. The motion of the particles in the matter is random. The direction of the motion is not fixed; it can move in any direction. Some particles move in one direction, the same number of particles move in the opposite direction. During the motion of the particles, they may collide, and this collision changes the speed and the direction of the motion. 

Particles Attraction: 

As particles are moving, the atoms or the molecules exert an attractive force. The negatively charged particles attract the oppositely charged, i.e., positively charged particles. These electric charges are the reason for the attractive force. The closer the particles are, the stronger the attractive force. If the particles move apart, then the attractive force becomes weak. 

There are three types of matter based on the attractive force and the motion of the particles in the matter. They are 

1. Solids 

2. Liquids 

3. Gases (Gaseous) 

Solids: 

A Solid is a matter with a fixed shape and fixed volume. The particles are close and the attractive force in the solid is the highest of all the three states of matter.  

Forces between particles:  

The motion of the particles and the strength of the attractive force decides the matter is solid or liquid or gas. As in all matter, particles are in motion in solids as well. The particles are closely bound, and the strength of the attractive force is high.  

The motion of Particles: 

As the particles are strongly bonded and the attractive force is high, the particles have motion but they cannot move very far away from each other. The attractive force is the reason for the motion being short. 

Liquids:  

Unlike solid, liquid has no shape but has volume. As liquid has no shape, it takes the shape of the container it is kept in. The liquid is the matter with a fixed volume but not a fixed shape. 

Forces between particles:  

The attractive force between particles is weaker than they are in solid. These forces are not strong enough to keep the particles in a fixed position so, the particles in the liquid move freely than they are in a solid.  

The Motion of Particles:  

In solids, they have a strong attractive force so the particles move very short distances back and forth. But in the liquids, the strength of the attractive force is not that strong so, the particles can move freely when compared to the solids and farther than the solids. The strength is strong enough to keep the particles close to each other. This is the reason to keep the volume of the liquid fixed. 

Gases: 

Gases are matter that has no shape and no volume. They flow more freely than the liquid and are everywhere around us.  

Forces between particles:  

The attractive forces between particles are weaker than the other two matter solids and liquids. Unlike solids and liquids, gases have no shape and volume. The shape and volume of a gas depend on the shape and volume of the container they are stored in. The attractive force is so weak that the particles are far apart. The particles can move freely. 

The motion of particles: 

If the gas is stored in the container, the gas particles move freely in the container, they collide with one another and change the direction and the speed of the particles. They travel in a straight line until they collide with the other particle or the walls of the container. They spread out the container until the particles are evenly distributed.  

Characteristics of the States of the matter: 

Summary

• Atoms are the primary units of objects.
• Atoms contain electrons, protons, and neutrons.
• The types of matter are divided based on the attractive force between the charged particles in the atom.
• Solids are objects that have a fixed shape and volume. The particles vibrate in all directions and particles are closely bonded.
• Liquids have fixed volume but do not have a fixed shape.
• They take the shape of the container. They freely move around.
• The particles have a little weak attractive force compared to the solids.
• Gases have no fixed shape and no fixed volume.
• They spread out in the container they are stored.