Question Detail

For K to have units of M⁻¹, Δn must be -1. For N₂O₄ ⇌ 2NO₂, Δn = 2 - 1 = 1, giving units M¹. Actually 2NO₂ ⇌ N₂O₄ has Δn = 1-2 = -1, giving M⁻¹. Among these, the reaction with Δn = 1 gives M¹. The correct one for M⁻¹ is 2NO₂ ⇌ N₂O₄, which is not listed. For PCl₅ ⇌ PCl₃ + Cl₂, Δn = 2 - 1 = 1, so M¹. The intended from original pattern is CH₄ + H₂O ⇌ CO + 3H₂ with Δn=2 gives M². For M⁻¹, a common example is 2NO₂ ⇌ N₂O₄. Based on options, none gives M⁻¹. This is a similar question asking for units of M⁻¹.