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A reaction is second order in carbon monoxide. If the concentration of carbon monoxide is made twice as large while all other conditions are unchanged, what happens to the reaction rate?
- It becomes four times as large
- It becomes twice as large
- It stays the same
- It becomes three times as large
Correct answer: It becomes four times as large
Solution
In a second-order reaction, the rate is proportional to the square of the concentration of the reactant. Therefore, if the concentration of carbon monoxide is doubled, the rate increases by a factor of two squared, resulting in a fourfold increase in the reaction rate.
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