alleryFor a first-order reaction, the half-life t_(1/2) is:
A0.693/k (independent of initial concentration)
BInversely proportional to [R]₀
CEqual to 1/k
D[R]₀/(2k)
Answer & Solution
Correct answer: A. 0.693/k (independent of initial concentration)
First-order **t_(1/2) = ln(2)/k = 0.693/k**.
**Independent of initial concentration** — a defining feature of first-order reactions.
(Zero-order t_(1/2) = [R]₀/(2k) — depends on initial concentration.)
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