Initial concentration of the reactant is 1.0M. The concentration becomes 0.9M, 0.8M and 0.7M in 2 hours, 4 hours and 6 hours respectively. Then the order of reaction is

By hit and trial method K0=xt  is constant then it is zero order reaction.K02 hrs =1-0.92=120M hr-1 K04 hrs =1-0.84 =120M hr-1 K06 hrs =1-0.76 =120M hr-1 since rate constant value for zero order reaction is constant,orderof reaction is zero