QSP TEST PAPER QUESTIONS AND
SOLUTIONS COMPLETE REVIEW MATERIAL
●● explain the differences between open and closed systems
Answer: both: exchange energy with surroundings
open: exchange matter with surroundings
closed: can not exchange matter with surroundings
●● explain why chemical equilibrium can only be achieved in closed
systems
Answer: this is because to achieve equilibrium, the concentrations must
be constant but if the reaction is losing matter to the surroundings, the
concentration is unable to stay constant
●● what is the differences between the energy profile diagrams of
exothermic and endothermic reactions
Answer: exothermic: downslope
endothermic: upslope
●● compare the rates of the forward and reverse reactions when a
chemical equilibrium has been established
Answer: equal
,●● compare the rates of the forward and reverse reactions when
approaching chemical equilibrium
Answer: forward = decreasing
reverse = increasing
●● activated complex
Answer:
●● activation energy
Answer: energy that is needed to get a reaction started
●● chemical change
Answer: a change in matter that produces one or more new substances
●● physical change
Answer: a change of matter from one form to another without a change
in chemical properties
●● collision theory
Answer: for a reaction to occur, the particles must collide, they must
collide with the appropriate orientation, and they must collide with
sufficient energy.
, ●● Le Chatelier's Principle
Answer: tates that if a stress is applied to a system at equilibrium, the
system shifts in the direction that relieves the stress.
●● partial pressure
Answer: the pressure exerted against the sides of the container by a gas
●● spontaneous
Answer: occurring without the heat
●● steady rate
Answer: equal rate
●● if Gibbs free energy is negative, the reaction is [spontaneous/not
spontaneous]
Answer: spontaneous
●● if Gibbs free energy is positive, the reaction is [spontaneous/not
spontaneous]
Answer: not spontaneous
●● if enthalpy is negative, the reaction is [endothermic/exothermic]
Answer: exothermic
SOLUTIONS COMPLETE REVIEW MATERIAL
●● explain the differences between open and closed systems
Answer: both: exchange energy with surroundings
open: exchange matter with surroundings
closed: can not exchange matter with surroundings
●● explain why chemical equilibrium can only be achieved in closed
systems
Answer: this is because to achieve equilibrium, the concentrations must
be constant but if the reaction is losing matter to the surroundings, the
concentration is unable to stay constant
●● what is the differences between the energy profile diagrams of
exothermic and endothermic reactions
Answer: exothermic: downslope
endothermic: upslope
●● compare the rates of the forward and reverse reactions when a
chemical equilibrium has been established
Answer: equal
,●● compare the rates of the forward and reverse reactions when
approaching chemical equilibrium
Answer: forward = decreasing
reverse = increasing
●● activated complex
Answer:
●● activation energy
Answer: energy that is needed to get a reaction started
●● chemical change
Answer: a change in matter that produces one or more new substances
●● physical change
Answer: a change of matter from one form to another without a change
in chemical properties
●● collision theory
Answer: for a reaction to occur, the particles must collide, they must
collide with the appropriate orientation, and they must collide with
sufficient energy.
, ●● Le Chatelier's Principle
Answer: tates that if a stress is applied to a system at equilibrium, the
system shifts in the direction that relieves the stress.
●● partial pressure
Answer: the pressure exerted against the sides of the container by a gas
●● spontaneous
Answer: occurring without the heat
●● steady rate
Answer: equal rate
●● if Gibbs free energy is negative, the reaction is [spontaneous/not
spontaneous]
Answer: spontaneous
●● if Gibbs free energy is positive, the reaction is [spontaneous/not
spontaneous]
Answer: not spontaneous
●● if enthalpy is negative, the reaction is [endothermic/exothermic]
Answer: exothermic
