Answer to Question #170511 in Chemistry for Hyeri

Question

In determining the reaction velocity for the reaction A + 2B ⇌AB2

Why must the concentration of B molecules be squared?

Answer 1

A + 2B ⇌AB₂

According to the rate of reaction equation:

r = k [A]^a [B]^b

where r - reaction rate, k - rate constant, [A]^a - concentration of a reactant [A] with power raised by its coefficient, [B]^b - concentration of a reactant [B] with power raised by its coefficient.

As [B] has a coefficient 2, [B] must be squared - [B]^b = [B]².