Question 22M.2.hl.TZ1.2a
| Date | May 2022 | Marks available | [Maximum mark: 2] | Reference code | 22M.2.hl.TZ1.2a |
| Level | hl | Paper | 2 | Time zone | TZ1 |
| Command term | Suggest | Question number | a | Adapted from | N/A |
Magnesium is a reactive metal often found in alloys.
Suggest an experiment that shows that magnesium is more reactive than zinc, giving the observation that would confirm this.
[2]
Alternative 1
put Mg in Zn2+(aq) ✔
Zn/«black» layer forms «on surface of Mg» ✔
Award [1 max] for “no reaction when Zn placed in Mg2+(aq)”.
Alternative 2
place both metals in acid ✔
bubbles evolve more rapidly from Mg
OR
Mg dissolves faster ✔
Alternative 3
construct a cell with Mg and Zn electrodes ✔
Accept “electrons flow from Mg to Zn”.
Accept Mg is negative electrode/anode
OR
Zn is positive electrode/cathode
bulb lights up
OR
shows (+) voltage
OR
size/mass of Mg(s) decreases <<over time>>
OR
size/mass of Zn increases <<over time>>
Accept other correct methods.
Mediocre performance; some experiments would not have worked such as adding magnesium to zinc salt without reference to aqueous environment, adding Zn to magnesium ions, or Mg combustion reaction being more exothermic. In the last one, an inference wad made instead of identifying an observation or measuring temperature using a thermometer or a temperature probe.
