Skip to content
MathsGenie logo
Open app

Course home

  1. A Level
  3. Chemistry AQA
  5. Question bank

Electrode potentials and electrochemical cells (A-level only)

EasyMediumHard
1234567891011
Question 2

Some standard electrode potential data are shown:

Co2+(aq)+2e−→Co(s)E⊖=−0.28 VCu2+(aq)+2e−→Cu(s)E⊖=+0.34 V \begin{aligned} \text{Co}^{2+}(\text{aq}) + 2\text{e}^- &\rightarrow \text{Co}(\text{s}) \quad E^\ominus = -0.28\text{ V} \\ \text{Cu}^{2+}(\text{aq}) + 2\text{e}^- &\rightarrow \text{Cu}(\text{s}) \quad E^\ominus = +0.34\text{ V} \end{aligned} Co2+(aq)+2e−Cu2+(aq)+2e−​→Co(s)E⊖=−0.28 V→Cu(s)E⊖=+0.34 V​

Which is a correct statement about this cell?

Co(s)∣Co2+(aq)∥Cu2+(aq)∣Cu(s) \text{Co}(\text{s}) \mid \text{Co}^{2+}(\text{aq}) \parallel \text{Cu}^{2+}(\text{aq}) \mid \text{Cu}(\text{s}) Co(s)∣Co2+(aq)∥Cu2+(aq)∣Cu(s)

The standard EMF of the cell is +0.06 V+0.06\text{ V}+0.06 V.

Electrons flow in the external circuit from the copper electrode to the cobalt electrode.

The concentration of cobalt(II) ions decreases as the cell discharges.

The mass of the copper electrode increases during the operation of the cell.

Electrode potentials and electrochemical cells (A-level only) Questions

  1. A Level
  2. /Chemistry
  3. /Electrode potentials and electrochemical cells (A-level only)