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

Options

A. 2
B. `-1`
C. 1
D. `-2`

Answer

D

Explanation

`r=k [A]^(n) [B]^(n)`
`r'=(r )/(4)=k[A]^(n) (2[B])^(n)" "rArr (r )/(r')=4=((1)/(2))^(n) rArr n=-2`