Form 5 Chemistry: Standard Electrode Potential

What does the // represents in a cell notation for a galvanic cell?

• a phase boundary

• a wire (metal) connection

• a salt bridge

• gas electrode

Which of the following statements is (are) true for all voltaic (or galvanic) cells?

I. Oxidation occurs at anode

II. The voltage is less than or equal to zero.

III. The cathode gains mass during the discharge

• I

• II and III

• I and III

• I, II and III

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

Sn²⁺ + 2e^- --> Sn⁴⁺ E⁰ = -0.14 V

Mg²⁺ + 2e^- --> Mg E⁰ = -2.37 V

• -2.23 V

• -2.51 V

• + 2.23 V

Which of the following is the cell notation for an electrochemical cell consisting of an anode where Mg (s) is oxidized to Mg2+(aq) and a cathode where Mn2+(aq) is reduced to Mn (s) . Assume all aqueous solutions have a concentration of 1 mol/L.

• Mg/Mg²⁺(1M) // Mn²⁺(1M)/Mn

• Mn/Mn²⁺(1M)//Mg²⁺(1M)/Mg

A voltaic cell using aluminium and nickel has the following notation.

Al(s)/Al³⁺(1M)//Ni²⁺(1M)/Ni(s)

Which of the following reaction occurs at anode?

• Ni(s) --> Ni²⁺ (aq)+ 2e

• Ni²⁺(aq) + 2e --> Ni

• Al(s) --> Al³⁺ + 3e

• Al³⁺(aq) + 3e -->Al

Calculate the cell potential of voltaic cell

• –1.51
• - 0.03
• +0.03
• +1.51

Voltaic cell is made by connecting two half-cells below. Which statement is correct?

• Mn is oxidised and voltage is 1.06 V

• Pb is oxidised and voltage is 1.06 V

• Mn is oxidised and voltage is 1.32 V

• Pb is oxidised and voltage is 1.32 V

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

What is the equation and cell potential?

• 2Al³⁺ + 3Ni → 2Al + 3Ni²⁺ E^O = 1.89 V
• 2Al + 3Ni²⁺ → 2Al³⁺ + 3Ni E^O = 1.89 V
• 2Al³⁺ + 3Ni → 2Al + 3Ni²⁺ E^O = 1.43 V
• 2Al + 3Ni²⁺ → 2Al³⁺ + 3Ni E^O = 1.43 V