Behaviour of Gases

The gas is one of the states of matter, and the gas has a large intermolecular space because it does not have a definite shape and is easily compressible. Temperature and pressure are certain factors that affect the behaviour of gases. The kinetic theory postulates several conditions for explaining the behaviour of gases and various factors affecting them. Several laws were framed to observe the behaviour of the gases, like Boyle’s Law, Charles’ Law, Gay Lussac’saw, etc. Based on these laws, the gas that follows the condition is called the ideal gas, and those which deviate from the laws are called non-ideal gas.

WHAT IS GAS?

Gases one of the states of matter along with solid and liquid. It is termed as a homogeneous liquid which has a low density as well as a low viscosity. The molecules of gases are far away from each other, due to which they do not have a definite volume. Several laws are postulated to determine the behaviour of gases in different situations depending on several factors.

WHAT IS BEHAVIOUR OF GAS?

Gas is a state of matter that has a large intermolecular space because of which it does not have a definite shape, and the particles of the gases move in a random motion. The behaviour of gas definition explains it as a change in the intermolecular space or the random motion of the particles under the influence of temperature or pressure of the gas. To study the behaviour of gases, there are a number of laws postulated, for example, Boyle’s law. Charles’ Law, Gay Lussac’s law, etc.

KINETIC THEORY OF GAS:

The kinetic theory of gas was framed to explain the behaviour of the gases under certain conditions. Kinetic theory mainly focuses on the microscopic observation of the gas, i.e., the observation of the gas molecules. The kinetic theory of gas puts forward several conditions. They are:

• The gases are composed of a number of molecules, and each molecule is moving in a random motion.
• The intermolecular space of the gas molecules is large, i.e., they have a large distance between each molecule.
• There is no interaction between the molecules of the gases, i.e., the intermolecular reaction is considered to be negligible.
• The molecules of the gases are considered to have kinetic energy, which is affected by the temperature change.

FACTORS AFFECTING THE BEHAVIOUR OF GAS:

Several factors affect the behaviour of gases. These factors are termed as.

• Temperature: It is said that the rise in temperature leads to the rise in the pressure of the gaseous molecules, i.e., the pressure change in the gas molecules is directly proportional to the temperature change.
• Volume: If we decrease the volume, the pressure will rise as the gas molecules adjust themselves in the confined area. Thus, the pressure of the gas molecules is inversely proportional to the volume.
• Pressure: If the pressure of the gas molecules is increased at a constant temperature, the volume of the gas is considered to decrease, i.e., the volume of the gas is inversely proportional to that of pressure.
• Quantity: If the number of molecules of gases is increased in a confined container, there will be a rise in pressure. Hence, the quantity of the gas molecules in a fixed volume determines the rise in the pressure.

GAS LAWS:

There are several gas laws postulated for studying the behaviour of gases. Some of the gas laws are:

• Boyle’s Law: According to Boyle’s law, the volume of the gas is inversely proportional to that of the pressure under the condition of constant temperature. Mathematically, the Boyle’s law is expressed as:

P ∝ 1/V

PV=Constant

Here, P denotes the pressure of the gas, and V denotes the volume of the gas.

• Charles Law: Charles Law states that the temperature is directly proportional to that of the volume of a gas, considering the mass is fixed. Mathematically, it is expressed as.

V ∝  T

Here, T stands for the temperature of the gas, and V denotes the volume of gas.

• Gay Lussac’s law: Gay Lussac’s law explains the relation of gas as, the pressure of the gas is directly proportional to the absolute temperature of the gas under the condition that the volume is constant. Mathematically, it is expressed as:

P∝T

There are other gas laws that need to be considered to study the behaviour of gases, for example, Avogadro’s law, Ideal gas law, etc.

CONCLUSION:

Gas is defined as one of the states of matter that have low density and viscosity. The intermolecular space is quite large, and the particles move in a random motion, which determines the behaviour of gases under the influence of temperature and pressure change. The basic gas laws, like Charles’ Law, Boyle’s law, etc., are postulated to explore the behaviour of gases. The behaviour of gases definition expresses the changes in a gas according to the proportional temperature and pressure change. On the basis of these laws, gas is categorised into two groups, Ideal gas, which is known as the perfect gas and non-ideal gas, which is termed as the real gas. After having certain knowledge of the behaviour of gases, it is required to have further knowledge about the gas compressibility factor and gas formation factor.