Assume that NO(g) reacts according to the rate expression rate=k[NO]^2[H2]
How does the rate change if
a) The concentration of H2 is doubled
b) The volume of the enclosing vessel is suddenly halved
c) The temperature is increased
a) The rate will be quadrupled (2^2) since the concentration of H2 is in the exponent of the rate expression and doubling it will result in the rate increasing by a factor of 2 raised to that exponent.
b) The rate will be doubled since the volume is inversely proportional to the concentration. Halving the volume will double the concentration of all reactants and the rate will follow suit.
c) It is not possible to determine the exact effect of an increase in temperature without knowing the activation energy of the reaction and the value of the rate constant at the new temperature. However, in general, an increase in temperature will increase the rate of the reaction due to an increase in kinetic energy and the likelihood of successful collisions between the reactant molecules.