6. Solving a chemistry problem

5. The conversion of N-chloroacetanilide to p-chloroacetanilide was monitored by titration of the former with potassium iodide. Determine the order and rate constant of the reaction based on the following data.
t0 10 60 70 120 130 180 190 240 250
VKJ, ml 49.3 46.7 35.5 33.5 25.75 24.4 18.6 17.6 13.4 12.7
Use the substitution method and the van´t Hoff differential method.