Answer
The possible oxidation and reduction half-reactions when magnesium is immersed in various solutions are as follows:
(i). In HCl, possible reactions are
Mg → Mg2+ + 2e- (oxidation)
2H+ + 2e- → H2 (reduction)
(ii) In an HCl solution containing dissolved oxygen, possible reactions are
Mg → Mg2+ + 2e- (oxidation)
4H+ + O2 + 4e- → 2H2O (reduction)
(iii) In an HCl solution containing dissolved oxygen and Fe2+ ions, possible reactions are
Mg → Mg2+ + 2e- (oxidation)
4H+ + O2 + 4e- → 2H2O (reduction)
Fe2+ + 2e-→ Fe (reduction)
Work Step by Step
The possible oxidation and reduction half-rections when magnesium is immersed in various solutions are as follows:
(i). In HCl, possible reactions are
Mg → Mg2+ + 2e- (oxidation)
2H+ + 2e- → H2 (reduction)
(ii) In an HCl solution containing dissolved oxygen, possible reactions are
Mg → Mg2+ + 2e- (oxidation)
4H+ + O2 + 4e- → 2H2O (reduction)
(iii) In an HCl solution containing dissolved oxygen and Fe2+ ions, possible reactions are
Mg → Mg2+ + 2e- (oxidation)
4H+ + O2 + 4e- → 2H2O (reduction)
Fe2+ + 2e-→ Fe (reduction)
