Question

At a certain temperature the rate of this reaction is first order in SO₃ with a rate constant of 0.208 s⁻¹:

2SO₃(g) → 2SO₂(g) + O₂(g)

Suppose a vessel contains SO₃ at a concentration of 1.36M.
Calculate the concentration of SO₃ in the vessel 7.30 seconds later. You may assume no other reaction is important. Round your answer to 2 significant digits.

Answer 1

0.30 M

Step-by-step explanation:

Using integrated rate law for first order kinetics as:

`[A_t]=[A_0]e^(-kt)`

Where,

`[A_t]` is the concentration at time t = ?

`[A_0]` is the initial concentration = 1.36 M

k is the rate constant = 0.208 s⁻¹

t = 7.30 seconds

So,

`[A_t]=1.36* e^(-0.208* 7.30)\ M=0.30\ M`