Question

Which of the reactions performed are redox reactions (1a, 1b, 2, 3a, 3b, 4, 5a, 5b)? (Hint: Look for changes in oxidation states of the elements.) List the reaction number of each redox reaction in the left column of the table below and complete the table, identifying each oxidized and reduced substance and its oxidation state before and after the reaction. (1 pt. each) Hint: 2, 3a, 3b, 3 will not be included Initial Final Initial Final Rxn # Atom Oxidized Atom Reduced Oxidation Oxidation Oxidation Oxidation State State State State 2 Fe rs)+ 3cucl2(aq) culs) 2 Fe Cls (aa) Na 112 2 Al (s) 3CUC2 laq)30v(s) +2 Alcl 3 (aq) 4-H202(a9) 0219)t20 (D) MgCl2 (aq)Hz lg) 5a-Mg(5) 2HCI (aq)Macl2 (aq) H2lg) Hocg)D2 (9) H201) 5b + 46

Answer 1

Rxn #	Atom oxidized	Initial Oxidation state	Final oxidation state	Atom reduced	Initial oxidation state	Final oxidation state
1 a	Fe	0	+3	Cu	+2	0
1 b	Al	0	+3	Cu	+2	0
4	O	-1	0	O	-1	-2
5 a	Mg	0	+2	H	+1	0
5 b	H	0	+1	O	0	-2

Consider reaction numbered 4 : H₂O₂ (aq) $\rightarrow$ 1/2 O ₂ (g) + H₂O (l)

In this reaction, oxidation state of O is -1 in H₂O₂ and 0 in O ₂ . Here oxidation state of oxygen is increased by 1 unit , hence O is oxidized.

In this reaction, oxidation state of O is -1 in H₂O₂ and -2 in H₂O . Here oxidation state of oxygen is decreased by 1 unit , hence O is reduced.