CART Equilibrium and Reaction Rates 3

Question 1

Le Chatelier's Principle predicts that for an exothermic reaction at equilibrium, increasing temperature will:

Accepted Answer

Shift equilibrium toward reactants

Answer

Adding heat to an exothermic reaction shifts equilibrium left (toward reactants) because heat acts as a product in the reaction.

Question 2

The reaction quotient Q is used to:

Accepted Answer

Predict which direction a reaction will proceed to reach equilibrium

Answer

Comparing Q to Kc predicts direction: if Q < Kc, reaction proceeds forward; if Q > Kc, reaction proceeds in reverse.

Question 3

Which statement about a catalyst is correct?

Accepted Answer

It provides an alternate pathway with lower activation energy

Answer

A catalyst works by providing an alternative reaction mechanism with a lower activation energy, speeding up the reaction without being consumed.

Question 4

For the equilibrium N₂O₄(g) ⇌ 2NO₂(g), adding more N₂O₄ will:

Accepted Answer

Shift equilibrium to the right to produce more NO₂

Answer

Adding more N₂O₄ increases reactant concentration, so Le Chatelier's Principle shifts equilibrium right to consume the added reactant.

Question 5

A reaction has Kc = 1.0 × 10⁻⁸. This very small value indicates that at equilibrium:

Accepted Answer

Reactants are highly favored

Answer

A very small Kc means the denominator (reactants) greatly exceeds the numerator (products), so reactants are strongly favored at equilibrium.

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