Apply: Le Châtelier's principle

Dinitrogen monoxide, commonly called “laughing gas,” has been used by dentists as an anesthetic since 1844.

At high temperatures and pressures, dinitrogen monoxide decomposes into nitrogen and oxygen gas:

2 N_{2} O (g) ⇌ 2 N_{2} (g) + O_{2} (g)

After reaching equilibrium, the volume of the reaction vessel is reduced by

10 %

Which direction does equilibrium shift, and why?

(Choice A)
Towards the reactant. The system must produce fewer gas molecules to lower the pressure.
(Choice B)
Towards the reactant. The increased pressure lowers the activation energy of the reverse reaction.
(Choice C)
Towards the products. The system must produce more gas molecules to raise the pressure.
(Choice D)
Towards the products. The increased pressure lowers the activation energy of the forward reaction.
(Choice E)
The system will not shift.

High school chemistry