Question

Be sure to answer all parts. Enter your answers in scientific notation. The following reactions have the indicated equilibrium constants at a particular temperature:
N2(g) + O2(g) ⇌ 2NO(g) Kc = 4.3 × 10−25 2
NO(g) + O2(g) ⇌ 2NO2(g) Kc = 6.4 × 109

Determine the values of the equilibrium constants for the following equations at the same temperature:
(a) 4NO(g) ⇌ N2(g) + 2NO2(g) × 10
(b) 4NO2(g) ⇌ 2N2(g) + 4O2(g) × 10
(c) 2NO(g) + 2NO2(g) ⇌ 3O2(g) + 2N2(g) × 10

Answer 1

Answer:

a) 1,5x10³⁴

b) 1,5x10¹⁵

c) 7,3x10¹⁴

Explanation:

It is possible to sum different reactions with its equilibrium constant to obtain the equilibrium constant of the new reaction, thus:

a) 2 NO(g) ⇄ N₂(g) + O₂(g) kc = 1/4,3x10⁻²⁵

+ 2 NO(g) + O₂(g) ⇄ 2 NO₂(g) kc = 6,4x10⁹

= 4 NO(g) ⇄ N₂(g) + 2NO₂(g) Where its equilibirum constant is:

1/4,3x10⁻²⁵ × 6,4x10⁹ = 1,5x10³⁴

b) 4 NO(g) ⇄ 2 N₂(g) + 2 O₂(g) kc = 2× 1/4,3x10⁻²⁵

4 NO₂(g)  ⇄ 4 NO(g) + 2 O₂(g) kc = 2× 1/6,4x10⁹

= 4 NO₂(g) ⇄ 2 N₂(g) + 4 O₂(g) Where its equilibirum constant is:

2× 1/4,3x10⁻²⁵ × 2× 1/6,4x10⁹ = 1,5x10¹⁵

c) 4 NO(g) ⇄ 2 N₂(g) + 2 O₂(g) kc = 2× 1/4,3x10⁻²⁵

2 NO₂(g)  ⇄ 2 NO(g) + O₂(g) kc =  1/6,4x10⁹

= 2NO(g) + 2 NO₂(g) ⇄ 2 N₂(g) + 3 O₂(g) Where its equilibirum constant is:

2× 1/4,3x10⁻²⁵ × 1/6,4x10⁹ = 7,3x10¹⁴

I hope it helps!