(a) Reaction is A $\rightarrow$ B for second order kinetics $(\text{Rate})_1 = K[A]^2$ $(\text{Rate})_2 = K[3A]^2 = 9K[A]^2$ $(\text{Rate})_2 = 9 \times (\text{Rate})_1$ So the rate of formation of $B$ will increase by 9 times. (b) The reaction that have higher order true rate law but are found to behave as first order are known as pseudo first order reactions. Example : Consider the acid hydrolysis of methyl acetate. $\mathrm{CH}_3 \mathrm{COOCH}_{3(\mathrm{ag})} + \mathrm{H}_2 \mathrm{O}_{(\mathrm{e})}$ $\rightarrow \mathrm{CH}_3 \mathrm{COOH}_{(\mathrm{ag})} +$ $\mathrm{CH}_3 \mathrm{OH}_{(\mathrm{ag})}$