Equilibrium and Le Chatelier's Principle

Which change would shift the equilibrium toward the products in the reaction CH4 (g) + 2 H₂S (g) ↔ CS₂ (g) + 4 H₂ (g)

• Increase concentration of methane (CH4)

• Decrease concentration of methane (CH4)

Which change would force the reaction to move in the reverse direction 3H₂(g)+N₂(g) <---> 2NH₃(g) ?

• Remove H2

• Add Catalyst

• Remove NH3

• Add H2

3H₂(g)+N₂(g) <----> 2NH₃(g) What is the equilibrium constant, Kc, for the reaction? Give your answer to the nearest tenth. [NH₃] = 0.41 M; [N₂] = 0.042 M; [H₂] = 0.104 M

• 2.81 × 10−4

• 93.86

• 3358

• 0.0107

Write the K_c equilibrium expression for the equation:

O₃ (g) + NO(g) <--> O₂(g) + NO₂(g)

• [O2] * [NO2]

• ( [O2] * [NO2] ) / ( [O3] * [NO] )

• ( [O2]^2 * [NO2] ) / ( [O3]^3 * [NO] )

• ( [O3] * [NO] ) / ( [O2] * [NO2] )

According to Le Chatelier's Principle, adding reactants to a chemical reaction at equilibrium will cause the reaction to __________________________________________________ (you need more than one word here – it's a phrase)

• Shift toward reactants

• Right

• Forward

• Shift toward products

PCl₅(g) <-->PCl₃(g) + Cl₂(g).

What is the equilibrium constant if the equilibrium concentrations are as follows: PCl₅ is 0.0096 mol/L, PCl₃ is 0.0247 mol/L and Cl₂ is 0.0247 mol/L?

• (0.0096) / (0.0247)^2 = 15.73

• (0.0247)^2 / (0.0096) = 0.0636

Write the K_c equilibrium expression for the equation: 2H₂O(g) → 2H₂(g) + O₂(g)

• [H2] * [O2] / [H2O]

• [H2]^2 * [O2] / [H2O]^2

• [H2]^2 * [O2]

• [H2O]^2 / [H2]^2 * [O2]

N ₂O₄ (g)+Energy ←➔ 2NO₂(g)

What action would NOT cause the equilibrium to shift?

• Adding NO2

• Increase Temperature

• Increase Pressure

• Adding catalyst

In an exothermic reaction, equilibrium shifts _______ when temperature is lowered

• Right

• Left

N ₂O₄ (g)+Energy ←➔ 2NO₂(g)

If pressure was increased, which direction would the equilibrium shift

• Right, toward products

• Left, toward reactants

• No change

• Not enough info given