A 10.0 mL aliquot of an acid-catalysed ester hydrolysis mixture is titrated with 0.100 M NaOH. The titres are 19.6 mL (t = 0), 31.6 mL (25 min) and 39.6 mL (infinite time); each mole of ester hydrolysed yields one mole of carboxylic acid. Find the initial rate of the reaction in units of $1 0^{- 3} mol L^{- 1} mi n^{- 1}$ (two decimals).

Numerical answer type, answer in 10^-3 mol L^-1 min^-1, tolerance 0.05.

Answer: 7.33 10^-3 mol L^-1 min^-1

[ester]_{0} = \frac{( V _{\infty} - V _{0} ) M}{v} = \frac{20.0 \times 0.100}{10.0} = 0.200

k = \frac{1}{25} ln \frac{20.0}{8.0} = 0.03665 mi n^{- 1}

. Initial rate

= k [ester]_{0} = 7.33 \times 1 0^{- 3} mol L^{- 1} mi n^{- 1}