DP Chemistry (last assessment 2024)
Question 19M.2.hl.TZ2.b(ii)
| Date | May 2019 | Marks available | [Maximum mark: 2] | Reference code | 19M.2.hl.TZ2.b(ii) |
| Level | hl | Paper | 2 | Time zone | TZ2 |
| Command term | Describe | Question number | b(ii) | Adapted from | N/A |
b(ii).
[Maximum mark: 2]
19M.2.hl.TZ2.b(ii)
Rhenium, Re, was the last element with a stable isotope to be isolated.
Before its isolation, scientists predicted the existence of rhenium and some of its properties.
A scientist wants to investigate the catalytic properties of a thin layer of rhenium metal on a graphite surface.
Describe an electrochemical process to produce a layer of rhenium on graphite.
[2]
Markscheme
electrolyze «a solution of /molten» rhenium salt/Ren+ [✔]
graphite as cathode/negative electrode
OR
rhenium forms at cathode/negative electrode [✔]
Note: Accept “using rhenium anode” for M1.
Examiners report
Generally well done; most described the cell identifying the two electrodes correctly and a few did mention the need for Re salt/ion electrolyte.
