DP Chemistry Unit 9 HL: Electrode potential and electrolysis

What are the features of a standard hydrogen electrode?

• H₂ gas at 100kPa

• [H⁺] = 1.00 M

• 273 K

• platinum electrode

Which represents reduction process occurring in standard hydrogen electrode?

• H_2(g) → 2H⁺_(aq) + 2e^–
• H⁺_(aq) + OH^–_(aq) → H₂O_(l)
• 2H⁺_(aq) + 2e^– → H_2(g)
• O_2(g) + 4H⁺_(aq) + 4e– → 2H₂O_(l)

Which statement is correct about value of E^ο?

• more positive value E^ο, greater driving force for reduction
• more negative value E^ο, greater driving force for reduction
• more positive value E^ο, greater the rate of reaction
• more negative value E^ο, greater the rate of reaction

Tags

NGSS.HS-PS2-5

Cr³⁺ +3e --> Cr E⁰ = -0.74V

Ag+ + e --> Ag E⁰ = +0.80 V

Based on the standard reduction potential for silver and chromium, is this a spontaneous process?

3 Ag⁺ + Cr --> 3 Ag + Cr³⁺

• Yes

• No

• depends on the temperature

Cr³⁺ +3e --> Cr E⁰ = -0.74V

Ag+ + e --> Ag E⁰ = +0.80 V

Based on the standard reduction potential for silver and chromium, calculate the cell potential for the following reaction

3 Ag⁺ + Cr --> 3 Ag + Cr³⁺

• +0.06 V

• -0.06 V

• 1.66 V

• +3.14 V

Calculate the cell potential of a galvanic cell that uses the two half equation below

Mg²⁺ + 2e^- --> Mg E⁰ = -2.37 V

Sn²⁺ + 2e^- --> Sn⁴⁺ E⁰ = -0.14 V

• -2.23 V

• -2.51 V

• + 2.23 V

• +2.51 V

During the electrolysis of a molten ionic substance, what is attracted to the anode

• anions, which are then oxidised

• anions, which are then reduced

• cations, which are then oxidised

• cations, which are then reduced

What are the products when molten potassium bromide is electrolysed?

• Anode: K (l)

  Cathode: Br₂ (g)

• Anode: Br₂ (g)

  Cathode: K (l)

• Anode: Br (g)

  Cathode: K (s)

• Anode: Br₂ (g)

  Cathode: H₂ (g)

During electrolysis of aqueous solutions the species reduced at the cathode are nearer the ______ of the table of standard electrode potentials.

What are the products during the electrolysis of H₂SO₄? (water)

• Anode: oxygen

  Cathode: hydrogen

• Anode: hydrogen

  Cathode: oxygen

• Anode: water

  Cathode: oxygen

• Anode: sulphur

  Cathode: hydrogen