STATES OF MATTER-I-GASES
KEY POINTS:
1. Kinetic molecular theory:
The kinetic molecular theory was postulated by Daniel Bernoulli, it explains the behavior of gases based on the movement of molecules.
2. Boyle's law:
According to Boyle's law, the volume of a fixed amount of a gas is inversely proportional to applied pressure at constant temperature and the number of moles.
\[V \propto \frac{1}{p}\; (When\; T\; and\; n\; are\; constant\; )\]
3. Charle's law:
According to Charle's law, the volume of a fixed amount of gas is directly proportional to absolute temperature at constant pressure and the number of moles.
\[V \propto T\; (When\; P\; and\; n\; are\; constant\; )\]
4. Avagadro's law:
According to Avagadro's law, the volume of a fixed amount of gas is directly proportional to the number of moles at constant temperature and pressure.
\[V \propto n\; (When\; P\; and\; T\; are\; constant\; )\]
5. Graham's law of diffusion or effusion:
According to Graham's law, the rate of diffusion or effusion of a gas is inversely proportional to the square root of density or molar mass of gas at constant temperature and pressure.
\[r \propto \frac{1}{\sqrt{d}}\;\;\;\; or \;\;\; r \propto \frac{1}{\sqrt{M}}\;\]
6. Dalton's law of partial pressure:
According to Dalton's law of partial pressure, the total pressure exerted by a mixture of non-reacting gases is equal to the sum of their partial pressures.
7. Absolute Zero:
It is a hypothetical temperature at which the volume of an ideal gas becomes zero. Its value is -273.16 degrees Celcius or zero kelvin.
8. General gas equation:
It is also called an ideal gas equation.
PV=nRT
9. Van der Waal's equation:
It is also called as real gas equation.
\[\left ( P\; + a\frac{n^2}{V^2} \right )\left ( V\;-\;nb \right )\; = \;nRT\]
10. Joule Thomson effect:
The sudden expansion of highly compressed gases into a region of low pressure causes cooling.
11. Ideal gas:
Gases that obey Boyle's and Charle's law at all conditions are ideal. There are no forces of attraction between molecules of an ideal gas.
12. Non-ideal gas or real gas:
Gases that obey Boyle's and Charle's law at all conditions are ideal. There are no forces of attraction between molecules of an ideal gas.
13. Plasma:
Plasma is a mixture of positive ions; negative electrons and neutral atoms. It is also called the fourth state of matter.