Consider a reaction
2A + B → Product
The rate law for above reaction is
Rate = [A]2 [B]
If volume of the Vessel is doubled, concentrations are halved. Then, new rate is given as
Rate = k[A/2]2 [B/2]
If volume of vessel is reduced to 1/4th, concentrations become 4 times.
Then, new rate is given as:
Rate = k[4A]2 [4B]
If at constant temperature, pressure is doubled, volume is reduced to half. Hence, concentrations are doubled.
Then, new rate is given as:
Rate = k[2A]2 [2B]
