a flask contains NH3 (1.73×10-4 M) N2 (4.48×10-2 M) and H2 (2.63×10-2 M) What is value of equilibrium constant for reaction at 794 K?

If the reaction is N₂(g) + 3H₂(g) ⇌ 2NH₃(g) ...... Kc

Equilibrium constant, Kc
= [NH₃]² / ([N₂][H₂]³)
= (1.73 × 10⁻⁴)² / {(4.48 × 10⁻²) × (2.63 × 10⁻²)³}
= 0.0367 (L²/mol²)


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If the reaction is 2NH₃(g) ⇌ N₂(g) + 3H₂(g) ...... Kc

Equilibrium constant, Kc
= ([N₂][H₂]³) / [NH₃]²
= {(4.48 × 10⁻²) × (2.63 × 10⁻²)³} / (1.73 × 10⁻⁴)²
= 27.2 (mol²/L²)