Question

The reaction 2 ClO2(aq) + 2 OH-(aq) ClO3-(aq) + ClO3-(aq) + H2O(l) was studied at a certain temperature with the following results:

Experiment	[ClO2(aq)] (M)	[OH-(aq)] (M)	Rate (M/s)
1	0.0494	0.0494	0.0450
2	0.0494	0.0988	0.0899
3	0.0988	0.0494	0.180
4	0.0988	0.0988	0.360

(a) What is the rate law for this reaction?

Rate = k [ClO2(aq)] [OH-(aq)]

Rate = k [ClO2(aq)]2 [OH-(aq)]

Rate = k [ClO2(aq)] [OH-(aq)]2

Rate = k [ClO2(aq)]2 [OH-(aq)]2

Rate = k [ClO2(aq)] [OH-(aq)]3

Rate = k [ClO2(aq)]4 [OH-(aq)]

(b) What is the value of the rate constant?

(c) What is the reaction rate when the concentration of ClO2(aq) is 0.0581 M and that of OH-(aq) is 0.100 M if the temperature is the same as that used to obtain the data shown above?

______M/s

Answer 1

if you double the concentration of OH-, the rate of the reaction also doubles as well. Hence order of the reaction is one according to OH

if you double the concentration of ClO2, the rate of the reaction increses forur times as well. Hence order of the reaction istwo according to ClO2

Hence

Rate = k [ClO2(aq)]² [OH-(aq)]

k = Rate / [ClO2(aq)]² [OH-(aq)]

k = 0.045 / [0.0494 ]² 0.0494

k = 373.2 M^-2 S^-1

(c) What is the reaction rate when the concentration of ClO2(aq) is 0.0581 M and that of OH-(aq) is 0.100 M if the temperature is the same as that used to obtain the data shown above?

R = 373.2 x 0.0581² x 0.1

R = 7.32 x 10^-3 M/s