Question

Which of the following relation is correct for a first order reaction?

(k $=$ rate constant; r $=$ rate of reaction; c $=$ conc. of reactant)

• A. $k=r\times c^2$
• B. $k=r\times c$
• C. $k=\frac{c}{r}$
• D. $k=\frac{r}{c}$

Answer 1

The correct option is D $k=\frac{r}{c}$

For first order,
$A\to B$
Rate $=k\left[A\right]$ where, $\left[A\right]$ is the concentration of reactant $A$

$\therefore K=\frac{r}{c}$

Where, $r=$ rate of reaction and $c=$ concentration of reactant