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The time for half life period of a certain reaction Products is 1 hour. When the initial concentration of the reactant ‘A’ is 2.0 mol L⁻¹, how much time does it take for this concentration to come from 0.50 to 0.25 mol L⁻¹ if it is a zero order reaction ?
- 4 h
- 0.5 h
- 0.25 h
- 1 h
Correct answer: 0.25 h
Solution
From t1/2 = [A]0/(2k): 1 = 2.0/(2k) -> k = 1.0 mol L^-1 h^-1. Going from 0.50 to 0.25 needs Δ[A] = 0.25, so t = 0.25/1.0 = 0.25 h.
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