Electrochemistry Quiz

Which species is oxidised in the reaction: CuCl₂ + Fe → FeCl₂ + Cu?

• Cu²⁺

• Fe

• Cl⁻

• Cu

In the half-equation MnO₂ + 4H⁺ + 2e⁻ → Mn²⁺ + 2H₂O, what is happening to Mn?

• Oxidation, Mn increases oxidation number

• Reduction, Mn decreases oxidation number

• Oxidation, Mn decreases oxidation number

• Reduction, Mn increases oxidation number

Which species is reduced in: Cu + Br₂ → Cu²⁺ + 2Br⁻?

• Cu

• Br₂

• Br⁻

• Cu²⁺

In redox processes, the oxidising agent is:

• Always reduced

• Always oxidised

• Always neutralised

• Always decomposed

Which equation represents oxidation?

• Fe²⁺ → Fe³⁺ + e⁻

• Cl₂ + 2e⁻ → 2Cl⁻

• Cu²⁺ + 2e⁻ → Cu

• 2H⁺ + 2e⁻ → H₂

What is the oxidation number of S in SO₃²⁻?

• +6

• +4

• +2

• -2

In the equation PbO₂ + SO₂ → PbSO₄, which element is reduced?

• Pb

• S

• O

• Both Pb and S

During electrolysis, reduction always occurs at:

• The anode

• The cathode

• Both electrodes

• Neither electrode

Why must an ionic compound be molten for electrolysis?

• To allow water to act as a solvent

• To let ions move freely

• To increase electrode surface area

• To stop decomposition

In electrolytic cell The anode is always:

• Positive

• Negative

• Neutral

• Both positive and negative