After how much time is there only 225. mmol left?

Question

Under certain conditions the rate of this reaction is zero order in hydrogen iodide with a rate constant of 0.0011 M•s^-1.

2 HI (g) -> H₂ (g) + I₂ (g)

Suppose a 250. mL flask is charged under these conditions with 450. mmol of hydrogen iodide. After how much time is there only 225. mmol left? You may assume no other reaction is important.

Be sure your answer has a unit symbol, if necessary, and round it to 2 significant digits.

Answer 1

Integrated rate law for zero order reaction is

[A] = [A]_o - kt

Plug in the given values and solve for t