Electrochemistry

Question 1

E° of cell

Answer 1

E° = E° RHS - E° LHS

Question 2

Equations of rechargeable Li cells

What occurs at each electrode?

Answer 2

Li+ + CoO2 + e- → Li+[CoO2]- +ve electrode

Li → Li+ + e- -ve electrode

Question 3

Discharge of Li ion cells

Answer 3

Li + CoO2 → Li+[CoO2]-

Question 4

Recharge of Li ion cell

Answer 4

Li+[CoO2]- → Li + CoO2

Question 5

Alkaline hydrogen oxygen fuel cell

What happens at each electrode?

Answer 5

-ve electrode: H2 + 2 OH- → 2 H2O + 2 e-

+ve electrode: O2 + 2 H2O + 4 e- → 4 OH-

Question 6

Alkaline hydrogen oxygen fuel cell

Overall equation

Answer 6

2 H2 + O2 → 2 H2O

Question 7

Acidic hydrogen oxygen fuel cell

Equations

Answer 7

H2 → 2 H+ + 2 e-

O2 + 4 H+ + 4 e- → 2 H2O

Overall: 2 H2 + O2 → 2 H2O