DP Chemistry (last assessment 2024)
Question 22N.2.sl.TZ0.3c.iii
Date | November 2022 | Marks available | [Maximum mark: 1] | Reference code | 22N.2.sl.TZ0.3c.iii |
Level | sl | Paper | 2 | Time zone | TZ0 |
Command term | Outline | Question number | c.iii | Adapted from | N/A |
c.iii.
[Maximum mark: 1]
22N.2.sl.TZ0.3c.iii
Consider the following reaction:
Cu2+ (aq) + Fe (s) → Fe2+ (aq) + Cu (s)
The diagram shows an unlabelled voltaic cell for the reaction:
Cu2+ (aq) + Fe (s) → Fe2+ (aq) + Cu (s)
(c.iii)
The diagram includes a salt bridge that is filled with a saturated solution of KNO3. Outline the function of the salt bridge.
[1]
Markscheme
«keep» each half-cell/electrolyte «electrically» neutral ✔
Accept balance charges/ions.
Accept allow ion flow «between cells».
Examiners report
The majority of the candidates outlined the function of the salt bridge. One of the common answers that did not score the mark was that the salt bridge allowed electrons to flow (without mentioning ions).
