Answer: The combined gas law is a combination of Boyle's Law and Charles' Law. The relationship between pressure, volume, and absolute temperature are all present in the combined gas law. It is written mathematically as:
PV/T=k (constant)
The constant, k, will also depend on the number of moles and could therefore vary. As long as the number of moles is constant, k, will be a true constant value.
Most combined gas law are worked with a before condition and an after condition. We typically number these conditions of state as 1 and 2 (sometimes initial and final also). So the working form of the combined gas law is:
P1V1/T1=P2V2/T2
Any units will work here for pressure and volume but the temperature must be absolute (Kelvin).
Explanation: