Chemistry

Problem

The gas-phase reaction

\mathrm{CO + NO_2 \rightarrow CO_2 + NO}

has an activation energy of

60\,\text{kJ mol}^{-1}

. At 300 K,

6\%

of collisions meet or exceed this energy, and only

4\%

of those energetic collisions have the required orientation (the carbon end of CO striking the nitrogen atom of

\mathrm{NO_2}

). Two independent strategies are proposed to increase the reaction rate: (a) Raise the temperature to 330 K, which increases the fraction of energetic collisions to

15\%

while leaving the orientation factor unchanged. (b) Use polarized laser light at 300 K to align the reactant molecules, raising the orientation factor to

12\%

while the energetic fraction remains

6\%

. Which of the following comparisons of the two strategies is most accurate? a) Strategy (b) produces a smaller increase in successful collisions than strategy (a). b) Both strategies increase the number of successful collisions by the same factor. c) Strategy (b) produces a larger increase in successful collisions than strategy (a). d) Strategy (a) roughly triples the number of successful collisions, whereas strategy (b) only about doubles it.

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