Question

The reaction: 2 NO + Cl2 2 NOCl

has been studied and found to be first order with respect to nitrogen monoxide and second order with respect to chlorine.
a. What is the overall order for the reaction?
b. How does the reaction rate change when the nitrogen monoxide concentration is doubled and the chlorine concentration is halved? Define terms (e.g., [NO]1 for initial concentration in experiment 1, [NO]2 for initial concentration in experiment 2, [NO]2 = 1?2 [NO]1), set up the rate law ratios and show cancellations for Exp2/Exp1
My Results: (Temp at 22 C for all at room temp)
Experiment 1: Flask 1= 1 min 19 sec , Flask 2 =1min 18sec
Experiment 2: Flask 1= 43 sec , Flask 2 = 44 sec

Answer 1

a. 3

b. The reaction rate is halved.

Step-by-step explanation:

The reaction: 2 NO + Cl₂ ⇄ 2 NOCl

has been studied and found to be first order with respect to nitrogen monoxide and second order with respect to chlorine.

a. What is the overall order for the reaction?

The overall order for the reaction is the sum of all the individual orders, that is, 1 + 2 = 3.

b. How does the reaction rate change when the nitrogen monoxide concentration is doubled and the chlorine concentration is halved?

The rate law for experiment 1 is:

`r_(1)=k.[NO]_(1).[Cl_(2)]_(1)^(2)`

The rate law for experiment 2 is:

`r_(2)=k.[NO]_(2).[Cl_(2)]_(2)^(2)=k.(2[NO]_(1)).(0.5[Cl_(2)]_(1))^(2) =0.5.k.[NO]_(1).[Cl_(2)]_(1)^(2)`

The ratio Exp 2/Exp 1 is:

`(r_(2))/(r_(1)) =(0.5.k.[NO]_(1).[Cl_(2)]_(1)^(2))/(k.[NO]_(1).[Cl_(2)]_(1)^(2)) =0.5`