When reaction 1) and 2) below are added together, the result is reaction 3).1) h2o (l) + hno2 (aq) ⇌ h3o + (aq) + no2 - (aq) k1 = 4.50 * 10-42) h3o + (aq) + oh - (aq) ⇌ 2 h2o (l) k2 = 1.00 * 10143) hno2 (aq) + oh - (aq) ⇌ no2 - (aq) + h2o (l) k3=? find the equilibrium constant, k3?

Chemical reaction 1:

H₂O (l) + HNO₂ (aq) ⇌ H₃O⁺ (aq) + NO₂⁻ (aq); K₁ = 4,5·10⁻⁴².

Chemical reaction 2:

H₃O⁺ (aq) + OH⁻ (aq) ⇌ 2H₂O (l); K₂ = 1,00·10¹⁴.

Chemical reaction 3:

HNO₂ (aq) + OH⁻ (aq) ⇌ NO₂⁻ (aq) + H₂O (l); K₃ = ?

Chemical reaction 3 is sum of chemical reaction 1 and chemical reaction 2:

K₃ = K₁ · K₂.

K₃ = 4,5·10⁻⁴² · 1,00·10¹⁴.

K₃ = 4,5·10⁻²⁸.