25. Solving a chemistry problem

8. When studying the reaction between pyridine and ethyl iodide
C6H5N C2H5I C7H10N I
for the same concentrations of the two reagents (0.1 M), the following data were obtained:
t,c 235 465 720 1040 1440 1920
[C6H5N]103, M 85 74 65 56 48 41
Prove that the reaction has a general 2nd order by the integral method (substitution method and graphical method) and find the rate constant. Calculate the half-life.