G11SBQ1

What is the coefficient for H⁺ in the following equation of redox reaction when the equation is balanced?

Zn + Cr₂O₇^2– + H⁺ → Zn²⁺ + Cr³⁺+ H₂O

• 10

• 12

• 14

• 16

What is the coefficient for SO₃²⁻ in the following equation of redox reaction when the equation is balanced?

SO₃²⁻ + MnO₄⁻ ⟶ SO₄²⁻ + Mn²⁺

• 2

• 3

• 5

• 6

Balance the following redox reaction

Cr₂O₇²⁻ (aq) + I⁻(aq) ⟶ Cr³⁺ (aq) + I₂(s)

• 6I⁻ + Cr₂O₇²⁻ ⟶ 3I₂ + 2Cr³⁺

• 6I⁻ + Cr₂O₇²⁻ ⟶ 3I₂ + 2Cr³⁺ + 7H₂O

• 6e⁻ + Cr₂O₇²⁻ ⟶ 2Cr³⁺

• 14H⁺ + 6I⁻ + Cr₂O₇²⁻ ⟶ 3I₂ + 2Cr³⁺ + 7H₂O

1. Under standard conditions, which of the following is the net reaction that occurs in the cell?

Cd(s)|Cd²⁺(aq) || Cu²⁺(aq)|Cu(s)

• Cu + Cd2+ →Cd + Cu2+

• Cu + Cd →Cu²⁺ + Cd²⁺

• Cu²⁺ + Cd²⁺ →Cu + Cd

• Cu²⁺ + Cd →Cu + Cd²⁺

Determine the cell notation for the redox reaction given below

Cd(s) + 2 Ag⁺(aq) → Cd²⁺(aq) + 2 Ag(s)

• Cd(s) ∣ Cd²⁺(aq) ∣∣ Ag⁺(aq) ∣ Ag(s)

• Ag⁺(aq) ∣ Ag(s) ∣∣ Cd(s) ∣ Cd²⁺(aq)

• Ag(s) ∣ Ag⁺(aq) ∣∣ Cd²⁺(aq) ∣ Cd(s)

• Cd²⁺(aq) ∣ Cd(s) ∣∣ Ag(s) ∣ Ag⁺(aq)

1. The cell notation for an electrochemical cell is: Co(s) | Co²⁺ || Cu²⁺ | Cu(s)

The left portion of the cell notation represents the

• anode

• cathode

• salt bridge

The equation of the overall cell reaction in a voltaic cell and the standard reduction potentials of the two half-reactions are given below. Write the cell notation for this voltaic cell.

I_2(s) + Fe_(s)⟶ Fe²⁺_(aq) + 2I^-_(aq

Half-reaction Standard Reduction Potential

I_2(s) + 2e⁻ ⇌ 2I^-_(aq) E° = + 0.536 V

Fe²⁺_(aq) + 2e⁻ ⟶ Fe_(s) E° = - 0.447 V

• Fe | I⁻ || I₂| Fe²⁺

• Fe | Fe²⁺ || I₂| I⁻

• I₂| I⁻ || Fe | Fe²⁺

• I₂ | Fe²⁺ || Fe | I⁻

In a voltaic cell, the half cell that receives anions from the salt bridge is

• Anode

• cathode

Below shows a cell diagram for voltaic cell. Which of the following is FALSE?

• Electrons flow from anode to cathode

• Oxidation happens in anode

• Copper undergo reduction to form copper ions

• Zinc undergo oxidation to form Zinc ions

What reaction occurs at the anode?

• Ag⁺ + e^- →Ag

• Ag → Ag⁺ + e^-

• Ni²⁺ + 2e^- → Ni

• Ni → Ni²⁺ + 2e^-