Aliquots of decomposing H2O2 solution are titrated with acidified KMnO4; the titre is proportional to [H2O2]. The titre falls from 40.0 mL at t = 0 to 25.0 mL at t = 10 min. For first-order decay the time (in min) at which the titre reaches 10.0 mL is

JEE Main levelSingle correct optionDifficulty 2 of 3ck125

Aliquots of decomposing $H X_{2} O X_{2}$ solution are titrated with acidified $KMnO X_{4}$ ; the titre is proportional to $[H X_{2} O X_{2}]$ . The titre falls from 40.0 mL at t = 0 to 25.0 mL at t = 10 min. For first-order decay the time (in min) at which the titre reaches 10.0 mL is

k = \frac{1}{10} ln \frac{40.0}{25.0} = 0.0470 mi n^{- 1}

. Then

t = \frac{1}{k} ln \frac{40.0}{10.0} = 29.5

min.