Hydrogen Iodide Decomposes at 800 K Via a Second-Order Process

Hydrogen iodide decomposes at 800 K via a second-order process to produce hydrogen and iodine according to the following chemical equation. 2HI(g) → H₂(g) + I₂(g)
At 800 K it takes 233 seconds for the initial concentration of HI to decrease from 5.75 × 10^-2 M to 2.50 × 10^-2 M.What is the rate constant for the reaction at this temperature?

A) 1.90 × 10^-4 M^-1s^-1
B) 9.70 × 10^-2 M^-1s^-1
C) 10.3 M^-1s^-1
D) 5.27 × 10³ M^-1s^-1