Question

The rate of reaction between two reactants A and B decreases by a factor of 4,if the concentration of reactant B is doubled. The order of this reaction with respect to reactant B is:

• A. -1
• B. -2
• C. 1
• D. 2

Answer 1

Answer: (B)

-2

Answer 2

The method below can be used to determine the response rate: rate = $K[A]^x \times[B]^y$
A is the concentration of reactant A, B I is the concentration of reactant B, x is the order of reaction with respect to A, and y is the order of reaction with respect to reactant B in the above formula.
The rate constant is given as k.
The relationship between the rate and concentration of the reactant is known as the order of reaction.
$\frac{r_1}{4}$ = $K[A]^x \times[B]^y$

$\frac{r_1}{4\times r_1}=(2)^y$

$\frac{1}{4}=(2)^y$

$\bigg(\frac{1}{2}\bigg)^2=(2)^y$

$(2)^{-2}-(2)^y$

$\therefore y = -2$

So, the correct option is (B): -2