Worksheet: Types of Equilibrium
In this worksheet, we will practice classifying equilibria as static or dynamic and as homogeneous or heterogeneous.
The following reaction occurs when a burner on a gas stove is lit: Which of the following statements is an accurate description of this reaction?
- AAn equilibrium is established because the reaction does not alter the number of moles of gas in the system.
- BAn equilibrium is established because carbon dioxide and water are already present in the air.
- CAn equilibrium is not established because the reaction is highly exothermic, preventing the temperature from reaching a constant value.
- DAn equilibrium is not established because the gas stove is not a closed system and the product gases can escape.
- EAn equilibrium is not established because the rate of the forward reaction is much greater than the rate of the reverse reaction.
If a reaction is reversible, when can it be said to have reached equilibrium?
- AWhen the reactants and the products have equal concentrations.
- BWhen the reactants are fully consumed.
- CWhen the concentrations of the reactants and products are equal.
- DWhen the rates of the forward and reverse reactions are equal.
- EWhen the concentrations of the products are equal to the standard value, typically 1 M.
Which of the following is the correct definition of a reversible reaction?
- AThe reaction can be undone with the right catalyst.
- BIf you reverse the flow of time, the reaction will undo itself.
- CThe forward reaction and the reverse reaction occur at the same rate.
- DThe reaction can proceed in both the forward and reverse directions.
- EA second reaction converts the products of the reaction back to reactants, resulting in a cyclic process.
Under standard conditions, a sealed container of bromine consists of a liquid phase in equilibrium with a gaseous phase. Why would it be impossible to establish an equilibrium between and if the container were not a closed?
- AIn an open system, the bromine would be consumed by reaction with air before the phases could equilibrate.
- BIn an open system, the container would empty due to rapid vaporization of .
- CIn an open system, it is always more favorable for the material to exist in the gas phase.
- DIn an open system, the rate of condensation is limited by diffusion of out of the container.
- EIn an open system, the rate of condensation is limited by variation of the boiling point with the liquid mass.
At the boiling point of a liquid, which of the following conditions is satisfied?
- AThe free energies of vaporization and condensation are equal in magnitude.
- BThe rate of evaporation equals the rate of condensation.
- CThe rate of evaporation equals the rate of convection.
- DVapor pressure equals atmospheric pressure.
- EVapor pressure equals the liquid surface tension.
For at and 1 atm and at and 1 atm, which of the following quantities must be equal for the two phases?
- AThe molar enthalpy (Hm)
- BThe molar entropy (Sm)
- CThe molar volume (Vm)
- DThe molar Gibbs free energy (Gm)
Heat is added to a block of ice in a bath of liquid water at . A student records the temperature of the ice and the mass of liquid water . The system remains at thermal equilibrium and ice remains at the end of the process. Which quantities do not change?
- ABoth and
- B only
- CNeither nor
- D only
- EMore information is needed.