Question

As an EPA scientist studying catalytic converters and urban smog, you want to find Kc for the following reaction: 2NO2(g) ⇋ N2(g) + 2 O2(g) Kc = ?. Use the following data to find the unknown Kc (1) ½ N2(g) + 1/2 O2(g) ⇋ NO(g) Kc = 4.8x10-10 (2) 2NO2(g) ⇋ 2NO(g) + O2(g) Kc = 1.1x10-5

Answer 1

Answer:

Kc = 4.774 * 10¹³

Explanation:

the desired reaction is

2 NO₂(g) ⇋ N₂(g) + 2 O₂(g)

Kc =[N₂]*[O₂]² /[NO₂]²

Since

1/2 N₂(g) + 1/2 O₂(g) ⇋ NO(g)

Kc₁= [NO]/(√[N₂]√[O₂]) →  Kc₁²= [NO]²/([N₂][O₂])

and

2 NO₂(g) ⇋ 2 NO(g) + O₂(g)

Kc₂= [NO]²*[O₂]/[NO₂]² →  1/Kc₂= [NO₂]²/([NO]²[O₂])

then

Kc₁²* (1/Kc₂) = [NO]²/([N₂]*[O₂]) *[NO₂]²/([NO]²[O₂])  = [NO₂]²/([N₂]*[O₂]²) = 1/Kc

Kc₁² /Kc₂ = 1/Kc

Kc= Kc₂/Kc₁² =1.1*10⁻⁵/(4.8*10⁻¹⁰)² = 4.774 * 10¹³