Finding the rate constant. Ap Chem Kinetics. Does the coefficient have any role in changing the rate constant. Specifically Question 1b.

Question

https://docs.google.com/document/d/1QzL1uTbyWNfh3_fEFKRDJx6QbTSP-n2pcDEsqhqMkQI/edit?usp=sharing

Answer 1

2NO(g) + Br₂(g) ==> 2NOBr(g)

Find order for NO:

Comparing experiments 1 and 2, [NO] doubles and [Br2] is constant. Rate increases 4x. =>2nd order

Find order for Br2:

Comparing experiments 1 and 3, [Br2] doubles and [NO] is constant. Rate doubles. => 1st order

a). Rate = k[NO]²[Br]

b). 9.6x10^-2 M/s = k[0.02]²[0.02] = 8.0x10^-6k

k = 12,000 M^-2s^-1

The coefficient in the balanced equation does not affect the rate constant, unless it is an elementary step.