No. of moles of gas is constant at combined gas law and pressure, temperature and volume is variable.
Gas laws tells about the behavior and characteristics of gas at different conditions.
According to this law at constant pressure, volume of the gas is directly proportional to the temperature of the gas, and it is represent as:
V ∝ T or V = kT, where k = gas constant.
According to this law pressure of the gas is directly proportional to the temperature of the gas, and it is represent as:
P ∝ T or P/T = k, where k = gas constant.
According to this law at constant temperature, pressure of the gas is inversely proportional to the volume of the gas, and it is represent as:
P ∝ 1/V or PV = k, where k = gas constant.
Combined gas law is the combination of all three above laws at constant moles of gas and it is represented as:
PV/T = k.
Hence, pressure and temperature is variables at Gay Lussac's Law.
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