Question

Problem 6.16

In the following reactions, identify what is oxidized, and what is reduced.

Part A

2Li(s)+F2(g)?2LiF(s)

	both Li and F are oxidized
	both Li and F are reduced
	Li is oxidized, F is reduced
	F is oxidized, Li is reduced

Cl2(g)+2KI(aq)?2KCl(aq)+I2(s)

	Cl is oxidized, K is reduced
	K is oxidized, Cl is reduced
	I is oxidized, Cl is reduced
	Cl is oxidized, I is reduced

Mg(s)+Cu2+(aq)?Mg2+(aq)+Cu(s)

	both Cu2+ and Mg are reduced
	both Cu2+ and Mg oxidized
	Cu2+ is oxidized, Mg is reduced
	Mg is oxidized, Cu2+ is reduced

Fe(s)+CuSO4(aq)?FeSO4(aq)+Cu(s)

	Fe is oxidized, Cu2+ is reduced
	S is oxidized, Fe is reduced
	Cu is oxidized, Fe is reduced
	SO4 is oxidized, Cu2+ is reduced

Answer 1

oxidation means when the Oxidation state increases.

reduction means when the Oxidation state is decreases.

1) 2Li(s)+F2(g)?2LiF(s)

lithium goes from 0 oxidation state(OS) to +1 OS

and F from 0 to -1

=> Li is oxidized, F is reduced (option C )

2) Cl2(g)+2KI(aq)?2KCl(aq)+I2(s)

Cl2 from 0 to -1

K from +1 to +1

I from -1 to 0

so, I is oxidized, Cl is reduced (option C)

3) Mg(s)+Cu2+(aq)?Mg2+(aq)+Cu(s)

Mg from 0 to +2

Cu from +2 to 0

=> Mg is oxidized, Cu2+ is reduced (option D )

4) Fe(s)+CuSO4(aq)?FeSO4(aq)+Cu(s)

Fe from 0 to +2

Cu from +2 to 0

SO4 from -2 to -2

=> Fe is oxidized, Cu2+ is reduced (option A)