Calculate the concentration

Question

Consider this reaction:

2SO₃(g) -> 2SO₂ (g) + O₂ (g)

At a certain temperature it obeys this rate law.

rate = (3.67 M^-1 .s^-1) [SO₃]²

Suppose a vessel contains SO₃ at a concentration of 0.970M. Calculate the concentration of SO₃ in the vessel 0.840 seconds later. You may assume no other reaction is important.

Round your answer to 2 significant digits.

Answer 1

Again, as with the other questions you are posting, you can tell the order from the rate law.

rate = k[SO₃]² tells us it is SECOND order with respect to [SO₃].

Now, just use the integrated rate law for a 2nd order reaction and solve for [SO₃] 0.84 s later

The integrated rate law for 2nd order is

1/[A] = 1/[A]_o + kt