at 25°c an aqueous solution will be acidic if a. [h3o+] > [h2o] b. [oh-] = [h3o+] c. [h3o+] >...

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At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7‑ M Answer: C

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Page 1: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• At 25°C an aqueous solution will be acidic if

a. [H3O+] > [H2O]

b. [OH-] = [H3O+]

c. [H3O+] > 10-7M

d. [OH-] > 10-7‑M

• Answer: C

Page 2: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• A weak acid is one which

a. Partially reacts with water

b. Does not react with coper

c. Only reacts with bases

d. Produces an aqueous solution with a pH greater than 7

• Answer: A

Page 3: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• The function of a salt bridge in a galvanic cell is to allow:

a. Electrons to flow from the cathode to the anode

b. Electrons to flow from the positive electrode to the negative electrode

c. Cations to flow to the cathode

d. Cations to flow to the anode

• Answer: C

Page 4: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• Coating steel with zinc metal is an example of

a. passive corrosion protection.

b. anodic corrosion protection.

c. sacrificial corrosion protection.

d. cathodic corrosion protection.

• Answer: C

Page 5: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• A supersaturated solution is one where the mass of solute dissolved in a given volume of solvent is

a. more than the mass of solute that is soluble at a given temperature.

b. equal to the mass of solute that is soluble at a given temperature.

c. less than the mass of solute that is soluble at a given temperature.

d. more than the maximum mass of solute that will dissolve at the standard temperature.

• Answer: C

Page 6: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• In a reduction oxidation, redox, reaction the reductant

a. loses electrons and is itself reduced.

b. is reduced and gains electrons.

c. gains electrons and is itself oxidised.

d. is oxidised and loses electrons.

• Answer: D

Page 7: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• When an aqueous solution of copper(II) sulfate is added to which one of the following aqueous solutions will a precipitate not be expected to form?

a. Sodium carbonate.

b. Barium chloride.

c. Ammonium chloride.

d. Silver nitrate.

• Answer: C

Page 8: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• The ammonium ion, NH4+(aq), is an acid. The conjugate base for this ion is

a. H2O(l).

b. NH3(aq).

c. OH-(aq).

d. NH2-(aq).

• Answer: B

Page 9: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• The oxidation number of Mn in the compound MnO4- is:

a. +7

b. –7

c. +8

d. –8

• Answer: A

Page 10: At 25°C an aqueous solution will be acidic if a. [H3O+] > [H2O] b. [OH-] = [H3O+] c. [H3O+] > 10 -7 M d. [OH-] > 10 -7 ‑ M Answer: C

• Which one of the following statements best describes why an aqueous solution of copper(II) sulfate will weakly conduct an electric current?

a. The copper(II) sulfate causes the water to ionise and these ions carry the electric current.

b. The copper(II) sulfate dissociates in water and the ions formed carry the electric current.

c. Copper(II) sulfate is an acid and when dissolved in water it forms H3O+ ions that carry the electric current.

d. The copper(II) sulfate releases electrons into the solution and these carry the current.

• Answer: B