Unit 7 Practice: Easy

Answer: A state where the forward and reverse reaction rates are equal.

Explanation: At equilibrium, reactions are still occurring in both directions.

The concentrations remain constant because the forward and reverse rates are equal.

Answer: No.

Explanation: Equilibrium means the concentrations are constant, not necessarily equal.

A reaction may have much more product than reactant, or vice versa.

Answer:

Kc = [C] / ([A][B])

Explanation: Products go in the numerator and reactants go in the denominator.

Each concentration is raised to its coefficient.

Answer:

Kc = [B] / [A]²

Explanation: The coefficient 2 becomes the exponent on [A].

Answer: No.

Explanation: The effective concentration of a pure solid is constant, so it is left out of the equilibrium expression.

Answer: No.

Explanation: Like pure solids, the concentration of a pure liquid is essentially constant.

Answer: Products are favored at equilibrium.

Explanation: A large K means the numerator of the equilibrium expression is much larger than the denominator.

Answer: Reactants are favored at equilibrium.

Explanation: A small K means relatively little product is present compared with reactants at equilibrium.

Answer: No.

Explanation: K tells you about the equilibrium position.

It does not tell you the reaction rate.

Reaction speed belongs to kinetics.

Answer: The reaction quotient.

Explanation: Q has the same mathematical form as K, but it can be calculated at any moment, not only at equilibrium.

Answer: Toward products.

Explanation: There are too few products compared with equilibrium.

The forward reaction occurs more strongly until Q becomes K.

Answer: Toward reactants.

Explanation: There are too many products relative to equilibrium.

The reverse reaction becomes favored.

Answer: The system is at equilibrium.

Explanation: The current concentrations already satisfy the equilibrium constant.

Answer:

Knew = 1/Koriginal

Explanation: Reversing the reaction flips the equilibrium expression.

Answer:

Knew = K²

Explanation: Every exponent in the equilibrium expression doubles.

Answer: Their K values are multiplied.

Explanation:

Koverall = K1 × K2

Answer: Temperature

Explanation: Changing concentration, pressure, volume, or adding a catalyst can shift the system, but only temperature changes the actual equilibrium constant.

Answer: When an equilibrium system is disturbed, it shifts in a direction that partially opposes the disturbance.

Explanation: The system responds to changes in concentration, pressure, volume, or temperature.

Answer: No.

Explanation: A catalyst speeds up both forward and reverse reactions.

It allows equilibrium to be reached faster but does not change K or the final equilibrium composition.

Answer: The solubility-product constant.

Explanation: Ksp describes the equilibrium between a slightly soluble ionic solid and its dissolved ions.