Question

The hydrolysis of ethyl acetate (CH3COOC2H5) by sodium hydroxide yields ethanol (C2H5OH) and sodium acetate (NaO2CCH3) by the reaction shown, which follows second order kinetics. In an experiment 500 mL of 0.1 M ethylacetate in water is mixed with 500 mL of 0.1 M NaOH in water. After 20 minutes the concentration of sodium acetate is measured and is 0.0435M. Determine the rate constant for the reaction.

Answer 1

(1/A)-(1/Ao) = kt

You know Ao and t from the problem. You can calculate A, subtitute and solve for k.
post your work if you get stuck.