J.R. S. answered 07/29/22
Ph.D. University Professor with 10+ years Tutoring Experience
PV = nRT ... ideal gas law
If you have two conditions for the gas, the initial condition and the final condition, you would have...
P1V1 = n1RT1 for the initial condition and
P2V2 = n2RT2 for the final condition
And since R is the gas CONSTANT, it will not vary (it's a constant), so we can write ...
P1V1 = n1T1 for the initial condition and
P2V2 = n2T2 for the final condition
Finally, we can relate these as follows:
P1V1 / n1T1 = P2V2 / n2T2
If the number of moles (n) is constant, we have ..,
P1V1 / T1 = P2V2 / T2 ... COMBINED GAS LAW
From this, we can derive Boyles law and Charles law ...
If T (temperature) is constant, we have
P1V1 = P2V2 ... BOYLE'S LAW
If P (pressure) is constant, we have
V1 / T1 = V2 / T2 ... CHARLES' LAW
If V (volume) is constant, we have
P1 / T1 = P2 / T2 ... GAY LUSSAC'S LAW
If T and P are constant, and the number of moles (n) changes, we have
V1/n1 = V2/n2 ... AVOGADRO'S LAW