Question

The mechanism of the reaction : $A + 2B + C \to D$ is
(step 1) (fast) equilibrium $A + B \rightleftharpoons X$
(step 2) (slow) $X + C\to Y$
(step 3) (fast) $Y+B\to D$
Which rate law is correct?

• A. $r=k\left[C\right]$
• B. $r=\left[A\right]\left[B\right]^{2}\left[C\right]$
• C. $r=k\left[A\right]\left[B\right]\left[C\right]$
• D. $r=k\left[D\right]$

Answer 1

Answer: (C)

$r=K\left[X\right]\left[C\right]$
$K'=\frac{\left[X\right]}{\left[A\right]\left[B\right]}$
$r=K' \left[A\right]\left[B\right]\left[C\right]$