The rate for the reaction OH–(aq) + HCN (aq) ®H2O (l) + CN–(aq) is first-order in both OH–and HCN concentrations, and the rate constant kat 25 °C is 3.7 × 109 L mol–1s–1. Suppose 0.500 L of a 0.0020 M NaOH solution is rapidly mixed with the same volume of a 0.0020 M HCN solution. Calculate the time (in seconds) required for the OH–concentration to decrease to a value of 1.0 × 10 4 M.