Complete Whole Notebook

12 Which action will drive the reaction to the right?
A heating the equilibrium mixture
B adding water to the system
C decreasing the oxygen concentration
D increasing the system’s pressure
Explanation: If one or more of the reactants is a gas then increasing pressure will effectively increase
the concentration of the reactant molecules and speed up the reaction. So, for gaseous reactants
only, pressure is essentially a concentration factor. Increasing pressure has virtually no effect on
solids or solutions engaged in a chemical reaction. The particles are, therefore on average, closer
together and collisions between the particles will occur more frequently.
NO2(g) + CO(g) ⇄ NO(g) + CO2(g)
13 The reaction shown above occurs inside a closed flask. What action will shift the reaction to the
left?
A pumping CO gas into the closed flask
B raising the total pressure inside the flask
C increasing the NO concentration in the flask
D venting some CO2 gas from the flask
Explanation: The reactants are favored which causes them to shift to left because there are no
gases present which means no change. The equilibrium will move in such a way that the
pressure increases again. It can do that by producing more gaseous molecules. In this case, the
position of equilibrium will move towards the left-hand side of the reaction.
NH4Cl(s) + heat ⇄ NH3(g) + HCl(g)
14 What kind of change will shift the reaction above to the right to form more products?
A a decrease in total pressure
B an increase in the concentration of HCl
C an increase in the pressure of NH3
D a decrease in temperature
Explanation: Increasing the temperature increases reaction rates because of the disproportionately
large increase in the number of high energy collisions. It is only these collisions (possessing at least
the activation energy for the reaction) which result in a reaction. When you raise the temperature of a
system, the molecules bounce around a lot more. They have more energy. When they bounce around
more, they are more likely to collide. That fact means they are also more likely to combine. When you
lower the temperature, the molecules are slower and collide less. That temperature drop lowers the
rate of the reaction.
15 In a sealed bottle that is half full of water, equilibrium will be attained when water molecules
A cease to evaporate.
B begin to condense.
C are equal in number for both the liquid and the gas phase.
D evaporate and condense at equal rates.
Explanation: At equilibrium, the rate of forward reaction is equal to the rate of backward reaction.
Therefore, when the rate of condensation will become equal to the rate of evaporation equilibrium is
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