Forms of Matter- Solid, Liquid and Gas for Class 3 Science

Everything around us is made up of matter. The matter is present in different forms. In this concept, different forms of matter in detail.

After reading the concept students will be able to-

• Discuss about the arrangements of atoms and molecules in the matter.
• Answer What is condensation.
• Define water evaporation.
• Explain the process of water cycle.

Each concept is explained to class 3 students using descriptions, illustrations, and concept maps. After you go through a concept, assess your learning by solving the two printable worksheets given at the end of the page.
Download the worksheets and check your answers with the worksheet solutions for the concept Forms of Matter- Solid, Liquid and Gas provided in PDF format.

 

Matter:

A matter is anything that possesses volume and weight and occupies space.

• A matter has a definite mass.
• It can be soluble or insoluble in water.
• Different things are made using one or more forms of matter.

Atoms and Molecules:

• Matter is made of very minute particles invisible to our eyes, called atoms.
• Atoms tend to move or vibrate.
• Two or more atoms strongly bond together and form bigger particles called molecules.

 

Forms of Matter:

Matters are present in three main forms—

1.Solid:

• • Solids have a specific weight, mass and definite shape.
  • These are visible and can be held.
  • A solid has a definite shape because its molecules are strongly held together.

 

2.Liquid:

• • A liquid can flow freely but has a definite mass.
  • The molecules of liquids are loosely held. Therefore, liquids are fluid in nature and can be poured.
  • They take the shape of the container in which they are poured.
  • Liquids do not have a fixed shape but have a fixed volume.

3.Gas:

• A gas does not have a specific shape and can flow freely in all directions.
• Gases feel lighter than solids and liquids as the molecules of gas are free to move in any direction.
• The atoms and molecules are not orderly arranged in gases.
• Gases do not have a fixed size, shape, or volume.

 

Changes in the Forms of Matter:

• Solids, liquids and gases can interchange among themselves due to factors like temperature and pressure.
• The conversion of a liquid to a gas when heated is called evaporation.
  Example:   Change of liquid water to water vapour.

• The conversion of a gas to a liquid when cooled is called condensation.

• The conversion of a liquid to a solid is called solidification.

• The conversion of a solid to a liquid due to the application of heat is called melting.

 

Water Cycle:

• The heat from the sunlight changes water from any water body into water vapour.
• The water vapour is lighter than the liquid water, due to which it moves in the upper layers of air.
• The air filled with water vapour reaches heights where the temperature is lower than the Earth’s surface, which condenses to form liquid water.
• The condensed water then falls on the Earth as rain, called precipitation.

 

Uses of Matter:

1.Uses of Solids:

1. • Solid wax is used in candles, crayons, etc.
   • Solid water, i.e., ice, is used to preserve the food items and in refreshing juices and drinks.
   • The pen, paper, pencil, bat, ball, cupboard and many things around us are solids.

2.Uses of Liquids:

• Liquid water is used for drinking, cooking, washing, etc.
• Liquid fuels such as petrol and diesel need to run the vehicles.
• We use liquid oil in diyas.
• Cooking oil is an essential part of our diet.

 

3.Uses of Gases:

• Oxygen helps in burning.
• Animals use oxygen to breathe, whereas plants use carbon dioxide to make food.
• The party balloons are filled with helium gas.

 

Mixtures of Different Forms:

• A combination of two or more substances of the same or different states is called a mixture.
• We often use mixtures of solids, liquids and gases.

Example:

 

New Words:

 

Did You Know?

• The air we breathe is composed of gases like nitrogen, oxygen, carbon dioxide, water vapour, etc.
• The snow on the mountain can directly convert into water vapour without melting into liquid water first.
• Fire is nothing but a mixture of hot gases.