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The time t1/4 is defined as the duration required for a reactant’s concentration to fall to three-fourths of its starting value. For a first-order reaction with rate constant K, t1/4 is given by
- 0.75/K
- 0.69/K
- 0.29/K
- 0.10/K
Correct answer: 0.29/K
Solution
For a first-order reaction, the time required for the concentration of a reactant to decrease to three-fourths of its initial value is derived from the first-order kinetics equation, leading to the specific relationship of t1/4 = 0.29/K.
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