DP Chemistry (last assessment 2024)

Test builder »

Question 18N.3.hl.TZ0.b

Select a Test
Date November 2018 Marks available [Maximum mark: 2] Reference code 18N.3.hl.TZ0.b
Level hl Paper 3 Time zone TZ0
Command term Formulate Question number b Adapted from N/A
b.
[Maximum mark: 2]
18N.3.hl.TZ0.b

Chemical energy from redox reactions can be used as a source of electrical energy.

Formulate half-equations for the reactions at the anode (negative electrode) and cathode (positive electrode) during discharge of a lithium-ion battery.

[2]

Markscheme

Anode (negative electrode):

Li (graphite) → Li+ (electrolyte) + e–

OR

LiC6 (s) → 6C (s) + Li+ (electrolyte) + e– ✔

 

Cathode (positive electrode):

Li+ (electrolyte) + e– + MnO2 (s) → LiMnO2 (s)

OR

Li+ (electrolyte) + e– + NiO2 (s) → LiNiO2 (s)

OR

Li+ (electrolyte) + e– + CoO2 (s) → LiCoO2 (s)

OR

2Li+ (electrolyte) + 2e– + 2CoO2 (s) → Co2O3 (s) + Li2O (s) ✔

 

Accept “polymer” for “electrolyte”.

Award [1 max] if electrodes are reversed.

Do not accept “CO” for “Co”.

Syllabus sections