Chapter 9 - Redox Review HL

A particular voltaic cell is made from magnesium and iron half-cells. The overall equation for the reaction occurring in the cell is Mg(s) + Fe²⁺(aq) → Mg²⁺(aq) + Fe(s)

Which statement is correct when the cell produces electricity?

• Magnesium atoms lose electrons

• The mass of the iron electrode decreases

• Electrons flow from the iron half-cell to the magnesium half-cell

• Negative ions flow through the salt bridge from the magnesium half-cell to the iron half-cell

Which statement is correct about the value of E^θ?

• The more positive the value the greater the driving force for reduction

• The more negative the value the greater the driving force for reduction

• The more positive the value the greater the rate of reaction

• The more negative the value the greater the rate of reaction

Consider the following reaction: H₂SO₃(aq) + Sn⁴⁺(aq) + H₂O(l) → Sn²⁺(aq) + HSO₄^-(aq) + 3H⁺(aq)

Which statement is correct?

• H₂SO₃ is the reducing agent because it undergoes reduction

• H₂SO₃ is the reducing agent because it undergoes oxidation

• Sn⁴⁺ is the oxidizing agent because it undergoes oxidation

• Sn⁴⁺ is the oxidizing agent because it undergoes reduction

Which equation represents the reduction process occurring in the standard hydrogen electrode?

• H₂(g) → 2H⁺(aq) + 2e^-

• H⁺(aq) + OH^-(aq) → H₂O(l)

• 2H⁺(aq) + 2e^- → H₂(g)

• O₂(g) + 4H⁺(aq) + 4e^- → 2H₂O(l)

Which processes occur during the electrolysis of molten sodium chloride?

I. Sodium and chloride ions move through the electrolyte II. Electrons move through the external circuit III. Oxidation takes place at the anode

• I and II only

• I and III only

• II and III only

• I, II, and III

What process occurs at the cathode in a voltaic cell and at the anode in an electrolytic cell?

• Oxidation occurs at a voltaic cell cathode and reduction occurs at an electrolytic cell anode

• Oxidation occurs at both the cathode in a voltaic cell and anode in an electrolytic cell

• Reduction occurs at a voltaic cell cathode and oxidation occurs at an electrolytic cell anode

• Reduction occurs at both the cathode in a voltaic cell and anode in an electrolytic cell

Which definition of oxidation is correct?

• Loss of electrons and a decrease in oxidation number

• Loss of electrons and an increase in oxidation number

• Gain of electrons and a decrease in oxidation number

• Gain of electrons and an increase in oxidation number

Which is the reducing agent in this reaction?

Cu(s) + 2NO₃^-(aq) + 4H⁺(aq) → Cu²⁺(aq) + 2NO₂(g) + 2H₂O(l)

• Cu(s)

• NO₃^-

• Cu²⁺

• H⁺

Which are redox reaction?

I. 2FeCl₂ + Cl₂ → 2FeCl₃ II. Mg + 2HNO₃ → Mg(NO₃)₂ + H₂ III. H₂O + SO₃ → H₂SO₄

• I and II only

• I and III only

• II and III only

• I, II, and III

In an electrolytic cell containing molten ZnCl₂ at which electrode will the chlorine form and what is the process taking place there?

• Positive, reduction

• Negative, reduction

• Positive, oxidation

• Negative, oxidation