Unit 3 AOS 2 Chemistry - Key Knowledge questions

Which of the following factors does NOT affect the rate of a chemical reaction?

• Temperature

• Surface area

• Concentration

• Atomic number

What is the primary role of a catalyst in a chemical reaction?

• To increase the yield of products

• To lower the activation energy

• To change the equilibrium constant

• To increase the reaction temperature

In an energy profile diagram, how does a catalyst affect the activation energy?

• It increases the activation energy

• It decreases the activation energy

• It has no effect on the activation energy

• It eliminates the activation energy completely

Which of the following best describes a reversible reaction?

• A reaction that cannot be undone

• A reaction that proceeds in only one direction

• A reaction that can proceed in both forward and reverse directions

• A reaction that always reaches completion

In a homogeneous equilibrium involving aqueous solutions, what does the double arrow (⇌) in the chemical equation represent?

• The reaction is irreversible

• The forward and reverse reactions are occurring simultaneously

• The reaction is incomplete

• The reaction is exothermic

According to Le Chatelier's principle, how would an increase in temperature affect an exothermic equilibrium reaction?

• It would shift the equilibrium to the right

• It would shift the equilibrium to the left

• It would have no effect on the equilibrium

• It would increase the equilibrium constant

What does the equilibrium constant (K) represent?

• The rate of the forward reaction

• The rate of the reverse reaction

• The ratio of products to reactants at equilibrium

• The activation energy of the reaction

How does the reaction quotient (Q) differ from the equilibrium constant (K)?

• Q represents the ratio of products to reactants at any point, while K is specific to equilibrium

• Q is always larger than K

• Q is temperature-dependent, while K is not

• Q applies only to reversible reactions, while K applies to all reactions

Which green chemistry principle is most closely related to the use of catalysts in industrial processes?

• Designing for energy efficiency

• Use of renewable feedstocks

• Atom economy

• Inherently safer chemistry

In the electrolysis of molten NaCl, what is produced at the cathode?

• Chlorine gas

• Sodium metal

• Hydrogen gas

• Oxygen gas