Question

Determine the rate law for $A+B\to C$ based on the following information.

$\left[A\right]$	$\left[B\right]$	Initial Rate (M/s)
$0.200$	$0.100$	$4.0\times {10}^{-3}$
$0.200$	$0.200$	$4.0\times {10}^{-3}$
$0.400$	$0.100$	$1.6\times {10}^{-2}$

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

Answer 1

Answer: (D)

$rate=k[A{]}^2$

Since it is clear by data
(i) When we double the conc. of A from 0.200 to 0.400 keeping B constant at 0.100, the rate doubled.
(ii) When we double the concentration of B from 0.100 to 0.200 keeping A constant to 0.200, the rate remains the same.

So $Rate=k[A{]}^2$ (not depend on B)