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Matter in our Surroundings

The matter in our surroundings is in three forms, i.e., solid, liquid, and gaseous forms. Ancient cultures believed matter included Air, Earth, Fire, Sky and Water.

Matter in our Surroundings

Scientists have developed two ways of categorising matter in our surroundings. The classification is as per its physical and chemical characteristics. The physical state of matter shows the particles in matter. The particles of matter have space between them and attract each other. Matter exists in three states: solid, liquid, and gaseous. We can transform each of these states into the other. We can apply pressure or modify the temperature to modify the physical condition of any substance. Changes in the state of matter include evaporation, condensation  and sublimation.

Physical Nature of Matter

The matter is made up of tiny particles which exhibit different properties.

Characteristics of Particles of Matter

  • They have space between them: This makes the particles of one type of matter enter the spaces between particles of the other. For example, sugar or salt gets evenly distributed in the water
  • They are continuously moving: Particles of matter continuously move as they possess kinetic energy
  • The kinetic energy also increases with the increase in temperature
  • Particles of matter get intermixed on their own by getting into the spaces between the particles. This intermixing of particles of two different types of matter by themselves is called diffusion
  • On heating, diffusion becomes faster
  • They attract each other: They have a force acting between them. This force keeps the particles together. This force of attraction varies in the different types of matter

States of Matter

The researchers divided the matter into five states, i.e., solid, liquid, gas, plasma and Bose-Einstein Condensate. Amid these states, the most familiar states of matter around us in the environment are solids, liquids and gases.

Solid-state

  • Solids have a definite shape, distinct boundaries and fixed volumes. They retain negligible compressibility
  • Solids tend to maintain their shape when subordinated to outside force. They may break under force, but it is difficult to change their shape; they are rigid

Liquid state

  • Liquids possess no fixed shape but have a fixed volume. They exhibit the shape of the container in which they are kept like a bucket, glass, etc
  • Liquids flow and change shape, so they are not rigid and thus are called fluid
  • Solids, liquids and gases can diffuse into liquids. The aquatic animals breathe underwater because of dissolved oxygen in the water
  • The diffusion rate of liquids is higher than that of solids since particles of liquids move freely and have more space between each other than particles of solids

Gaseous state

Gases are highly compressible when compared to solids and liquids.

  • Liquefied petroleum gas (LPG) used for cooking or the oxygen supplied to hospitals in cylinders is the compressed gas
  • Compressed natural gas (CNG) is used as a fuel in most vehicles

Due to high compressibility, we can compress large volumes of gas into a small cylinder, and thus transportation becomes easier.

Change in the state of matter

A matter can exist in any state. The states of matter are interconvertible and can be changed to other state forms by changing temperature or pressure accordingly. For example, water exists in all three states of matter: ice (solid), water (liquid) and water vapour (gas). 

Effect of change of temperature

Substances change their state from solid to liquid and from liquid to gas on the application of heat.

Effect of change of pressure

We can convert gas into liquid by applying pressure and reducing temperature. By applying pressure, we can bring particles of matter close together. Increasing or extending pressure and reducing temperature can liquefy gases.

The solid carbon dioxide that is CO2 is stored under high pressure. It gets converted directly to a gaseous state on pressure to decrease to 1 atmosphere without advancing into a liquid state. Therefore, it is also known as dry ice.

Therefore, pressure and temperature determine the state of a substance, whether it’s solid, liquid or gas.

Evaporation

The conversion of a liquid into gas on the application of heat is known as evaporation. The factors that affect evaporation include temperature and surface area. As the temperature increases, the speed of evaporation also increases. With the increase of temperature, many particles get enough kinetic energy to go into the vapour state. Temperature and rate of evaporation are directly proportional. Evaporation is a surface phenomenon. As the surface area increases, the speed of evaporation also increases.

Conclusion

The matter in our surroundings supports various properties like physical properties and chemical properties. The properties and characteristics are based on states of matter, i.e. solids, liquids or gases. The matter comprises particles that attract each other and have space between them. All the states of matter are interchangeable with the help of contributing factors, such as temperature and pressure. However, the nature of matter remains a large field of study, and recent advances have revealed new states of matter. The Boson-Einstein condensate and plasma are two more states of matter that scientists have recently discovered.