Learn Important Points on Physical Properties of Gases.

Introduction

Gas is considered one of the four fundamental states of matter. The other three include solid, liquid, and plasma. It is that state of matter in which the particles are very far from each other. The particles do not get attracted to one another and thus move around quickly, so the gas is much less dense than solids and liquids. The diagram will give you a clear view of the distance of particles in solid, liquid, and gas. The gas has no shape, size, definite volume, and colour. It takes the shape of the container it has been put into. Now, you will further learn about the various Physical Properties of Gases.

What Are Ideal Gases?

An ideal gas is described as a hypothetical or a theoretical gas composed of particles with randomly moving points. It is not subjected to interparticle interactions. It occupies negligible space. An ideal gas follows the laws of gas exactly and at all pressure and temperature. Some examples such as nitrogen, hydrogen, oxygen, carbon dioxide and a mixture like air are ideal gases that can be treated under reasonable tolerances. It has been explored in both kinetic theory and quantum mechanics. Since the name defines its quality, an ideal gas is also called a perfect gas.

What are the Physical Properties of Gases?

Apart from the characteristics of gases in their shape, size, volume and several other Physical Properties of Gases are there to read and understand.

• Compressibility

The first property deals with compressibility and yes, the gas can be compressed. The low density of gases makes it easy to get compressed. The compression is because the molecules set apart come together to generate an interatomic force of attraction in a sufficient amount between these molecules. This scenario is somehow similar to the molecular spacing and interaction. The compressibility is defined in the form of equation as,

Z= PV/RT

Where,

Z is compressibility

P is the pressure inside the molecules of gas

V is the volume of gas

T is the temperature of Kelvin

R is the universal gas constant

• Temperature 

The molecules of gases gain super and high kinetic energy when the temperature is roused in terms of gases. As a result, the molecules start colliding with one another and a collision occurs with the walls of the container. When the temperature is decreased, the molecules come closer, the volume of the gas increases and the pressure decreases.

• Expandability

As the pressure and volume of a gas are inversely proportional to each other, it is seen that by decreasing the volume of the gas, the pressure increases and thus the gas can be faster passed through the pipeline. With the increase in temperature, the kinetic energy gets high, resulting in a faster gas supply. Therefore, pressure and temperature inversely vary from each other.

• Low Density 

It is much less dense than the states of liquid and gas. This is because they contain scattered molecules and have larger intermolecular spaces in comparison with the other two. It also has larger volumes when compared to the mass of gas.

• Diffusibility

As the spaces between the gas molecules are larger, they can easily mix and thus form a homogenous mixture. This defines the diffusion and the property of diffusibility.

Hence, these are the important Physical Properties of Gas.

The Laws of Gases

The laws of gas are defined as laws that govern the behaviour of gases and relate pressure exerted on walls of a container by gas, its absolute temperature and the volume occupied by the gas.

There are several laws of gas that different scientists developed towards the end of the 18th century.

• Boyle’s Law: 

In this law, there is a relation between the volume and gas pressure. It is given at a constant temperature. The volume and pressure are inversely proportional at a constant temperature.

• Charles’s Law

This law states that the volume of gas is directly proportional to the temperature at a constant pressure in a closed system. It’s a relation portrayed between temperature and volume of the gas.

• Gay-Lussac Law

It states that there is a relation between the temperature and pressure at a constant volume. The pressure and temperature of the gas are directly proportional to one another at a constant volume.

• Avogadro’s Law 

In this, there is the same number of molecules in the system when the gas present is the ideal gas. Moreover, it is observed that if the gas volume is equal, no. of molecules will be the same as an ideal gas only when the volume is equal.

The combined gas law is obtained by combining all the four discussed and listed above laws.

Conclusion

Hence, these physical properties of gases laws given by different scientists will help you understand the gases and how they were portrayed in several ways in terms of volume, temperature and pressure. The different observations give you an overall view of this state of gas and differentiate between the solid and liquid.