A flask contains a mixture of compounds A and B. Both compounds decompose by first-order kinetics. The half-lives for A and B are 300 s and 180 s,…

A flask contains a mixture of compounds A and B. Both compounds decompose by first-order kinetics. The half-lives for $\displaystyle A$ and B are $\displaystyle 300$ s and $\displaystyle 180$ s, respectively. If the concentrations of A and B are equal initially, the time required for the concentration of A to be four times that of B (in s) is : (Use $\displaystyle \ln 2=0.693$ )