The liquid$-$phase reaction

Trityl $(A)+$ Methanol $(B)$ Products $(C)$

was carried out in a batch reactor at $25C$ in a solution of benzene and pyridine in an excess of methanol $)=(0\mathrm{.}5\frac{\text{m}\text{o}\text{l}}{d}{m}^3.$ Pyridine reacts with $HCl,$ which then precipitates as pyridine hydrochloride thereby making the reaction irreversible. The reaction is first order in methanol. The concentration of triphenyl methyl chloride $($A$)$ was measured as a function of time and is shown below.

$\backslash$table$[[t(min),0,50,100,150,200,250,300],[C_A(mo\frac{l}{d}{m}^3),0\mathrm{.}05,0\mathrm{.}038,0\mathrm{.}0306,0\mathrm{.}0256,0\mathrm{.}0222,0\mathrm{.}0195,0\mathrm{.}0174]]$

Use the integral method to confirm that the reaction is second order regarding triphenyl methyl chloride. State any assumptions that you are making while figuring out the order of reactant A$.$