For a first-order process A → B, if the rate constant is k and the starting concentration of A is 0.5 M, what is the half-life?

log 2 / k
log 2 / k√0.5
ln 2 / k
0.693 / 0.5k

Correct answer: ln 2 / k

Solution

The half-life of a first-order reaction is independent of the initial concentration and is given by the formula t1/2 = ln(2) / k, which reflects the constant rate at which the reactant A is converted to product B.

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