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Teach me all the kinetic theories of gases and their formulas explain evaporation and boiling and state their differences
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## Kinetic Theory of Gases
Key Postulates:
1. Gas molecules are in constant, random motion.
2. The volume of the gas molecules is negligible compared to the volume of the container.
3. Gas molecules do not exert forces on each other, except during collisions.
4. Collisions between gas molecules are perfectly elastic (no energy loss).
5. The average kinetic energy of gas molecules is directly proportional to the absolute temperature.
Formulas:
Ideal Gas Law: PV = nRT (where P = pressure, V = volume, n = moles, R = ideal gas constant, T = temperature)
Root-mean-square speed (Urms): Urms = √(3RT/M) (where M = molar mass)
Average kinetic energy (KEavg): KEavg = (3/2)kT (where k = Boltzmann constant)
## Evaporation vs. Boiling
Evaporation:
Occurs at any temperature.
A process where liquid molecules with enough kinetic energy escape from the liquid surface and enter the gas phase.
The rate of evaporation increases with temperature.
Boiling:
Occurs at a specific temperature (boiling point) for a given pressure.
A process where vaporization occurs throughout the liquid, not just at the surface.
The boiling point is the temperature at which the vapor pressure of the liquid equals the external pressure.
Differences:
Location: Evaporation occurs at the surface, while boiling occurs throughout the liquid.
Temperature: Evaporation can happen at any temperature, while boiling occurs at a specific boiling point.
Pressure: Evaporation is independent of pressure, while boiling depends on external pressure.
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