Answer:
half-life is 3.67s
Explanation:
The general law of the second-order reaction is:
[tex]\frac{1}{[A]}=\frac{1}{[A]_0}+kt[/tex]
As after 90.0s, the concentration of NO2 decreases from 0.500M to 0.0196M:
[tex]\frac{1}{[0.0196]}=\frac{1}{[0.500]}+k*90.0s[/tex]
49.02M⁻¹ = K*90.0s
0.5447M⁻¹s⁻¹ = K
Now, half-life, t1/2 is:
[tex]t_{1/2}=\frac{1}{K[A]_0}[/tex]
Half-life is:
t(1/2) = 1 / (0.5447M⁻¹s⁻¹*0.500M)
