AP Chemistryeasymcq1 pt
A reaction obeys the rate law rate = k[X]^2. If [X] triples while k and all other conditions stay constant, the rate becomes:
A.9 times larger
B.3 times larger
C.unchanged
D.6 times larger
Explanation
Core Concept
Second-order dependence means the rate scales with the square of the concentration. Tripling [X] contributes a factor of 3^2 = 9. The rate constant itself is unchanged because it depends on temperature, not on concentration. Squaring the multiplier is the whole task: three raised to the second power fixes the new rate at nine times its old value.
Correct Answer
A9 times larger
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