Chemical Equilibrium 1

This symbol indicates that a reaction is ____________

• reversible

• irreversible

• constant

• same rate

When the rate of the forward reaction is equal to the rate of backward reaction, the system is said to be in

• Chemical Equilibrium
• Chemical Balance
• Stoichiometry
• Chemical Reaction

At what time the reaction reached equilibrium?

• t₁
• t₂
• t₃
• t₄

At elevated temperatures ammonium carbonate, NH₂COONH₄, is in equilibrium with NH₃ and CO₂ according to the equation;

NH₂COONH₄(s) ↔ 2 NH₃(g) + CO₂(g)

What is the equilibrium expression for this reaction?

• K = 2 [NH₃][CO₂]

  [NH₂COONH₄]

• K = [NH₃]²[CO₂]

  [NH₂COONH₄]

• K = 2 [NH₃][CO₂]

• K = [NH₃]²[CO₂]

What kind of equilibrium does the reaction below show?

H_2(g) +I_2(g) ↔ 2HI_(g)

• Heterogeneous equilibrium, all the reactants and products are in the same physical state.

• Homogeneous equilibrium, all the reactants and products are in the same physical state.

• Heterogeneous equilibrium, the reactants and products are present in more than one physical state

• Homogeneous equilibrium, the reactants and products are present in more than one physical state

What are the two factors to look for when determining if the reaction is at equilibrium?

• Forward reaction rate is faster than the reverse and concentrations are equal
• Forward and reverse reaction rates are equal and concentration is conctant
• Forward and revers reaction rates are equal and concentration is equal
• Forward reaction rate is faster than the reverse and concentration is equal

Identify the incorrect statement about achieving equilibrium.

• achieved when product and reactant concentrations are equal

• achieved when forward and reverse reaction rates are same

• achieved when concentration of reactants is stable/constant

• achieved when concentration ratio of reactants to products becomes stable, thus fixing the equilibrium constant (equilibrium position)

2A + 3B  <---->  2AB
The forward reaction points towards the __________.

• left
• right
• up
• down

Identify the labels (a) and (b) on the graph.

• a is concentration of reactants and b is the concentration of product
• a is concentration of product and b is the concentration of reactant
• a is the volume of reactants and b is the volume of product
• a the mass of reactants and b is the mass of product

Which of the two graphs reaches equilibrium?

• The left one.
• The right one.
• Both of them.
• Neither.