1. Which of the following statements about conduction of electricity by compounds are true?

I. All compounds conduct electricity when molten or aqueous
II. Covalent compounds do not conduct in any state
III. Ionic compounds do not conduct when solid

 
  • A.   I and II only
  • B.   I and III only
  • C.   II and III only
  • D.   I, II and III
2.Which of the following statements is true?
  • A.   Covalent compounds conduct when liquid as molecules are free to move
  • B.   Ionic compounds conduct in aqueous solution as ions are free to move
  • C.   Covalent compounds do not conduct when solid as ions are not free to move
  • D.   Ionic compounds conduct when molten as electrons are free to move

3. Which is true about the ion attracted to the cathode?

  Type of ion Charge on ion
A anion positive
B anion negative
C cation positive
D cation negative
4. Which of the following substances is an electrolyte?
  • A.   copper metal
  • B.   solid sodium chloride
  • C.   copper(II)chloride solution
  • D.   molten sugar
5. Which of these elements could be formed at the anode during the electrolysis of a molten compound?
  • A.   iodine
  • B.   copper
  • C.   hydrogen
  • D.   sodium

6. What are the products of electrolysis of molten aluminium oxide ?

  Positive electrode Negative electrode
A aluminium oxygen
B aluminium hydrogen
C oxygen aluminium
D hydrogen aluminium
7. Which statement about the electrolysis of molten lead(II)bromide is correct?
  • A.   The anode is coated in a brown metal
  • B.   A brown gas forms at the cathode
  • C.   Bubbles of colourless gas are seen at the anode
  • D.   A bead of grey metal forms at the cathode
8. The diagram shows the apparatus for electroplating an iron nail with silver.

electrolysis of silver nitrate

Which row in the table below is correct?

  
  Terminal X is ... Electrode Z is made from ...
A positive carbon
B positive silver
C negative  carbon
D negative silver

9. Molten magnesium chloride was electrolyzed.

Which row gives the correct half-equation for the reaction at the cathode and the type of reaction occurring?

  Half-equation Type of reaction
A Mg2+ → Mg + 2e- oxidation
B Mg2+ → Mg + 2e- reduction
C Mg2+ + 2e- → Mg oxidation
D Mg2+ + 2e- → Mg reduction