Question

For the following reaction, it is found that doubling the amount of A causes the reaction rate to double while doubling the amount of B causes the reaction rate to quadruple. What is the best rate law equation for this reaction?

A + B 2C

Answer 1

what did you try?

you need to find these exponents (k,j)

\[rate=[A]^{k}[B]^{j}\]

Assume you try [A]=[B]=1, rate =1

they tell you rate doubles when you double [A]

\[rate=2=(2)^k(1)^j\]

here were focusing on k, (and since [B] remains constant we can ignore it)

when k=1, the rate is consistent with the rate law

when [B] doubles, i.e. [B]=2, the rate quadruples (we can ignore [A] since it's constant)

\[rate=4=(1)^k(2)^j\]

what should j be?