Question

The reaction rate between reactants Z and Y is proportional to the cube of [Z]. What is the rate law for this reaction?

Answer 1

Base on the problem given, it shows that the rate law for this reaction is directly proportional. The relationship between the reactants Z and Y that is proportional to the cube of [Z], it shows the concentrations of reactants is expressed by the rate law. 

Answer 2

Answer: $Rate=k[Z]^3$

Explanation:

Rate law says that rate of a reaction is directly proportional to the concentration of the reactants each raised to a stoichiometric coefficient determined experimentally called as order.

$Z+Y\rightarrow products$

$Rate=k[Z]^x[Y]^y$

k= rate constant

x = order with respect to Z = 3

y = order with respect to Y = 0

n = x+y = Total order

Thus rate law is written as: $Rate=k[Z]^3[Y]^0$  or $Rate=k[Z]^3$