Final NB 2016-2017 Turley

4 Which statement explains why the speed of some reactions is increased when the surface area of
one or all the reactants is increased?
A increasing surface area changes the electronegativity of the reactant particles
B increasing surface area changes the concentration of the reactant particles
C increasing surface area changes the conductivity of reactant particles
D increasing surface area enables more reactant particles to collide
catalyst
C6H6 + Br2 → C6H5Br + HBr
5 Which of the following changes will cause an increase in the rate of the above reaction?
A increasing the concentration of Br2
B decreasing the concentration of C6H6
C increasing the concentration of HBr
D decreasing the temperature
2CO + O2 → 2CO2
6 If the above reaction takes place inside a sealed reaction chamber, then which of these procedures
will cause a decrease in the rate of reaction?
A raising the temperature of the reaction chamber
B increasing the volume inside the reaction chamber
C removing the CO2 as it is formed
D adding more CO to the reaction chamber
7 A catalyst can speed up the rate of a given chemical reaction by
A increasing the equilibrium constant in favor of products.
B lowering the activation energy required for the reaction to occur.
C raising the temperature at which the reaction occurs.
D increasing the pressure of reactants, thus favoring products.
8 Which reaction diagram shows the effect of using the appropriate catalyst in a chemical reaction?
A
C
B
D
9 H2O2, hydrogen peroxide, naturally breaks down into H2O and O2 over time. MnO2, manganese
dioxide, can be used to lower the energy of activation needed for this reaction to take place and, thus,
increase the rate of reaction. What type of substance is MnO2?
A a catalyst
B an enhancer
C an inhibitor
D a reactant
143