Question

methane and hydrogen sulfide react to form carbon disulfide and hydrogen, like this:
ch₄(g)+2h₂s(g)→cs₂(g)+4h₂(g)
suppose a mixture of ch₄, h₂s, cs₂ and h₂ has come to equilibrium in a closed reaction vessel. predict what change, if any, the perturbations in the table below will cause in the composition of the mixture in the vessel. also decide whether the equilibrium shifts to the right or left.

Explanation:

Step1: Le Chatelier's Principle for Adding \(H_2S\)

According to Le Chatelier's principle, when a reactant (\(H_2S\)) is added, the equilibrium will shift to the right (towards the products) to consume the added \(H_2S\). As the equilibrium shifts to the right, \(CH_4\) (a reactant) is consumed, so its pressure decreases. And \(CS_2\) (a product) is formed, so its pressure increases.

Step2: Le Chatelier's Principle for Removing \(H_2\)

When a product (\(H_2\)) is removed, the equilibrium will shift to the right (towards the products) to produce more \(H_2\). As the equilibrium shifts to the right, \(CH_4\) (a reactant) is consumed, so its pressure decreases. And since the reaction is moving forward to make more products (including \(H_2\) by consuming \(H_2S\)), the pressure of \(H_2S\) decreases.

Answer:

• For "Some \(H_2S\) is added":
• The pressure of \(CH_4\) will decrease.
• The pressure of \(CS_2\) will increase.
• Shift in equilibrium: to the right.
• For "Some \(H_2\) is removed":
• The pressure of \(CH_4\) will decrease.
• The pressure of \(H_2S\) will decrease.
• Shift in equilibrium: to the right.