GAS LAWS

INTRODUCTION:
It is the fact that the gases have not fixed volume or shape and their volume can be change by the increase or decrease the pressure or temperature.the behaviour of a gas is described by the four variables pressure, volume, temperature and the mass of a gas.

BOYLES's LAW:

INTRODUCTION:

The law was given by Robert Boyle in 1660. He found experimently the relation between the Pressure and Volume at constant Temperature.

STATEMENT:

"For a given mass of a gas the volume is inversely proportional to the pressure exerted by it when the temerature of a gas is kept constant"

MATHEMATICALLY :

Let 'V' is the Volume of a gas which exerts a pressure 'P' on its surrounding at constant.       
Then According to the Boyle's Law

   V α 1/P 

OR

VP= Constant

that is the product of the pressure and volume is constant at constant temerature.

FOR N states of a GAS:

Consider N states of gas where the pressure and volume changes but temperature is kept constant.

P1V1=P2V2=P3V3..............PNVN

Where:

P1=Pressure at 1st state

P2=Pressure at 2nd state

P3=Pressure at 3rd state

PN=Pressure at Nth state 

V1=Volume at 1st state

V2=Volume at 2nd state

V3=Volume at 3rd state

VN=Volume at Nth state

if the mass of gas is not kept constant.

   P1V1/m= P2V2/m = P3V3/m =............. PnVn/m

where 'm' is the mass of a gas.

GRAPHICALLY:

let we take pressure at Y-axis and the Volume at X-axis then the Graph will be:

The Hyperbolic Curve is formed.

CHARLES LAW:

INTRODUCTION:

The law is given by CHARLES as known as the charles law which gives the relation between the volume and Temperature at Constant Pressure.

STATEMENT:

"For a given mass of a gas the volume is directly proportional to the temperature of a body when the pressure is kept constant"

MTHEMATICALLY:

let us consider a gas has a volume 'V" and at temerature 'T' where as the pressure of the gas is kept constant"

then according to the charles law:

V α T

OR

V/T = constant
that is the ratio of volume and pressure is constant at constant temperature.

FOR N STATES OF GAS:

V1/T1 =V2/T2 = V3/T3..........Vn/Tn

If the mass of gas is not constant then,

                              V1/mT1 =V2/mT2 = V3/mT3..........Vn/mTn

GRAPHICALLY: