# Gas Laws and Properties of Gases in Chemistry

In this post, we shall learn about Gass Laws and Properties of Gases in Chemistry. Gass Law and Properties of Gass is the most important part of Chemistry. Before we start let’s see what we are cover today – ( See the table of contents below )
 Gas Laws Properties of Gases

## Properties of Gases

(A) There is no specific size or volume of gaseous material. The container that holds it covers the entire volume of the vessel. The religion of gas molecules is the constant spread around. The flow of gas is seen only for the motion of the molecules.
(B) Gas molecules have much less ability to attract each other. With the slight change in pressure and heat, the volume of the gas changes substantially.
(C) If the pressure is applied to the gas in constant heat or if the pressure is increased by increasing the heat, the volume of the gas is compressed.
(D) Two or more gases that do not react to each other spontaneously mix with each other. The religion of gas diffusion says.
(E) The density of the gas is much lower than that of solid and liquid materials.
(F) Although there is a difference of chemical religion and nature between the different gases, the physical properties of all the basic or compound gases are the same.

## Pressure of  Gas

The closed gas exerts a force on the wall of the vessel. The force applied to the ball on every single area of ​​the wall is called gas pressure. The pressure of the gas is expressed by the height of the mercury column in the barometer device. Pressure of a gas = 76 cm mercury – This is to say, the pressure of that gas is equal to the height of 76 cm and the weight of a square with 1 sq. Ft.

## Standard Pressure

The evaporative pressure that applies a 76 cm mercury at 45o latitude and OoC warming at sea level is called proof pressure or one atmospheric pressure . Therefore, one-atmospheric pressure = 76 cm per hour pressure = 76 x 13.6 (mercury density) x 980 (gravitational acceleration) = 1.013 x 106 dyne / sqm = 1.013 x 105 Newton / sqm. The international unit of pressure is Pascal, Pa. = Newton / sqm. Thus, one-atmospheric pressure = 1.013 x 105 Pa. There is also the use of bar and torr unit to release pressure. 1 bar = 105 Pa and 1 tor = 1 mm pressure at the foot.

## Gas laws

The formula for the change in volume of a gas with the change of pressure and heat is called the formula of gas.

[1] Boyle’s Law: – If the temperature is constant, the volume of gas, the gas pressure in any given mass varies with the byastanupate.

• The mathematical form of Boyle’s formula: If the volume of gas of a certain mass is V and its pressure is P, then V of the Boyle formula
∝ 1/ P, If the warmth persists. Or, PV = constant. If the pressure of a certain mass of gas in constant heat is P1, P2, P3, and the volume is V1, V2, V3, etc., then according to Boyle’s formula P1V1 = P2V2 = P3V3 = K (constant).

[2] Charles’ Law’s: – pressure is fixed, the size of the mass of gas per degree Celsius increase in temperature or temperatures 0-degree C to reduce the volume of the gas, its 1/273The portions increase or decrease, respectively. 1/273The fraction is called the volume expansion coefficient of gas at constant pressure.

## Explanation of the formula

According to Charles’ formula, suppose the volume of a certain mass of gas at 0-degree-C heat = Vo.

So according to Charles’s point,

The volume of gas at 1-degree Celsius heat
The volume of gas at 2-degree Celsius heat

## The Absolute Scale of Temperature and Absolute Zero

Absolute Zero: – Charles can be seen from the formula, 0-degree-C to reduce the temperature of the mass of the volume of gas , Where Vo = 0-degree-C is the volume of that gas in heat. If the warmth can be reduced from 0-degree-C to 273-degree-C; That is, the gas volume is heated to

That means the gas will not occupy any volume during that heat.

The above phenomenon indicates minimum warming, given that the heat of a certain mass does not occupy any volume. Although it is possible in numbers, in reality it is impossible. Before the volume is practically zero, the gas becomes liquid. Regardless of the numerical rule, it is not possible to imagine a temperature lower than -273-degree-C, because then the volume of the gas is negative. Negative volume is meaningless. So it can be said that in the world no warming can be less than -273-degree-C. For this reason -273-degree-C warming is called extreme or absolute zero warmings.

• Definition: According to Charles’s formula, no gas of a certain mass of heat occupies a volume; That is, the volume is zero — it is called absolute zero warmth.

The absolute scale of heat or Kelvin scale: – 273-degree-C is the absolute scale of warmth, or the Kelvin scale when the temperature is equal to one degree Celsius and the degree of heat is equal to one degree Celsius. If 1 degree Celsius and 1 Absolute scale equal degree C, any heat on the Celsius scale will be converted to toC absolute scale, T = (273 + t) K. According to this scale, the absolute warmth is denoted by the uppercase T and the Kelvin (K) unit is expressed (not Ko). So, on this scale, the freezing point of water is 0-degree-C= 273K, the boiling point of water is 100-degree-C = 373K, and any warming t-degree-C = (273 + t) K = TK.

## Alternative form of Charles’s law

According to Charles’s formula, the volume of a specific mass of gas at t 1degree-C heat
Now-
Again, the volume of gas of a certain mass at t 2oC heat
Now-
By equation
Constant at constant pressure
That is, the volume of a gas at a certain mass at constant pressure is proportional to its absolute heat this is Charles’s formula, according to the absolute scale.

## Standard Temperature and Pressure, STP

76 ° C pressure and 0oC or 273K heat together are called proof pressure and heat (STP).

## An ideal gas equation or equation of state

The combination of Boyle and Charles PV = KT The constant K value of the equation depends on the gas mass. For one gas, that is, one mole, the value of constant K is the same for any gas. This constant is expressed with the letter R. The constant R is called the universal gas constant or the molar gas constant. In the case of a mole gas, the PV = RT equation is called the ideal gas equation or the equation of conditions. The ideal gas equation for n -mol gas is PV = nRT

Universal gas constant: – The value of constant R of the standard gas equation PV = RT does not depend on the nature and religion of the gas. It is the same for all gases. Therefore, R is called a universal gas constant. R = 8.31 x 107 arg / mole K = 8.31 zol / mole K; Since 1 Jul = 107 arg.

## The Motion of Gas Molecules

The assumptions made in gas, gases are:

[i] Small molecules of a gas are all solid elastic spheres.
[ii] All molecules of the same gas are the same.
[iii] The total volume of gas molecules is negligible compared to the volume of gas.
[iv] No attraction or repulsion force exists in the molecules of the gas – they have no stability and their energy is completely kinetic.
[v] Molecules are constantly moving and their collisions are stable, so momentum and kinetic energy are preserved.
[vi] The collision between molecules is instantaneous.
[vii] The paths between the two consecutive collisions are a straight line — that distance is called the free path.

## Evidence in Favour of Molecular Motion

[i] Diffusion of gas Due to religion, a small amount of gas spreads everywhere in any size vessel.
[ii] For the religion of religion, one of the fragrant oils kept inside the house spreads at the moment.
[iii] The gas molecules enclosed in a vessel push the wall of the vessel forward, causing pressure on the vessel wall. All these facts prove that the molecules of the gas are in constant motion.

## Dependence of Pressure on the Motion of Gas Molecules

The molecules continue to hit the walls of the vessel to keep the gas-molecules moving. This causes a change in momentum and causes stress on the vessel wall. Gas pressure is the measure of the force of a collision force on a single area of ​​a wall of a vessel. As the molecules speed up, the pressure also increases. The amount of pressure thus created depends on the average velocity of the molecules. If the average speed is threefold, the pressure will increase nine times. In a word, the motion of a gas molecule is the cause and pressure is the result.

## Dependence of Temperature on the Motion of Gas Molecules

As the speed of the gas-molecules increases, the heat of the gas increases, while the speed decreases. The reason for this is that – as the gas molecules increase, the kinetic energy increases and this excess kinetic energy is converted into heat energy. The current theory of gas shows that the average kinetic energy of each gas-molecule is proportional to the absolute heat of the gas. That is, heat is the amount of energy released by the molecules of a gas, and the average kinetic energy of each molecule of gas is the amount of heat.

## Ideal Gas and Real Gas

Ideal Gas: – the gas fully adhere to their commitments gatiya theory of the ideal gas is. From the theory of gas, Boyle’s formula can be corroborated by Charles’s formula. That is, all the gas that Boyle’s formula adheres to Charles’ formula is the ideal gas.
Real gas: – the gas source Boyle, Charles, do not adhere properly to their sources of real or actual gas to be. Gases knew as hydrogen, oxygen, nitrogen is called real gases. In fact, the existence of ideal gas is mere imagination. Only at high temperatures and low temperatures do real gases behave almost like an ideal gas and obey the ideal gas equations.