Two gaseous reactants A and B were placed in a reaction vessel in a dim room. the reaction was known to be photocatalytic. They react as shown. A + B ---> C + D. ∆H= -210Kjmol-¹

describe the effect on the rate of reaction when the conditions are changed as follows:

(a) the pressure is halves
b) the temperature is increased
c) The reaction is conducted in a bright room
D) The concentration of A is doubled​