A zero-order reaction has a half-life of 10.0 minutes when the reactant concentration is 0.250 M.How many minutes will it take for the reaction to be 75.0% complete?

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For a zero-order reaction, the half-life depends on the initial concentration of the reactant. The formula for the half-life of a zero-order reaction is $ t_{1/2} = \frac{[A]_0}{2k} $, where $ [A]_0 $ is the initial concentration and $ k $ is the rate constant. Since the half-life is given as 10.0 minutes for a 0.250 M concentration, we can find the rate constant $ k $ as $ k = \frac{[A]_0}{2t_{1/2}} = \frac{0.250}{2 \times 10} = 0.0125 \, \text{M/min} $.For the reaction to be 75% complete, the concentration of the reactant would decrease to 25% of its original value, i.e., to $ 0.250 \times 0.25 = 0.0625 \, \text{M} $. The change in concentration ($ \Delta [A] $) is $ 0.250 - 0.0625 = 0.1875 \, \text{M} $.Since the rate of a zero-order reaction is given by $ -\frac{d[A]}{dt} = k $, the time $ t $ required for this change is $ t = \frac{\Delta [A]}{k} = \frac{0.1875}{0.0125} = 15.0 \, \text{minutes} $.

A Zero-Order Reaction Has a Half-Life of 10