In the presence of excess thiocyanate ion, SCN−, the following reaction is first order in iron(III) ion, Fe3+; the rate constant is 1.27/s.
What is the half-life in seconds? How many seconds would be required for the initial concentration of Fe3+ to decrease to each of the following values: 25.0% left, 12.5% left, 6.25% left, 3.125% left? What is the relationship between these times and the half-life?
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