Question

At what time will B be present in greatest concentration?

• A. $\frac{k_{1}}{k_{2} - k_{1}}$
• B. $\frac{1}{K_{1} - K_{2}}In\frac{k_{1}}{k_{2}}$
• C. $\frac{1}{K_{2} - K_{1}}In\frac{k_{1}}{k_{2}}$
• D. None of these

Answer 1

Answer: (B)

$\frac{1}{K_{1} - K_{2}}In\frac{k_{1}}{k_{2}}$

Answer 2

$y = \frac{k_{1}a}{k_{2} - k_{1}}\left\lbrack e^{- k_{1}t} - e^{- k_{2}t} \right\rbrack$

$\frac{dy}{dt} = 0.$

$\text{- }\text{k}_{1}e^{\text{-k1t}}\text{ + }\text{k}_{2}e^{\text{-k2t}}\text{ = 0}$

So ${t\frac{1}{K_{1} - K_{2}}\frac{k_{1}}{k_{2}}}_{\max}$