DP Chemistry (last assessment 2024)
Question 19M.2.hl.TZ2.4d(ii)
| Date | May 2019 | Marks available | [Maximum mark: 2] | Reference code | 19M.2.hl.TZ2.4d(ii) |
| Level | hl | Paper | 2 | Time zone | TZ2 |
| Command term | Calculate | Question number | d(ii) | Adapted from | N/A |
d(ii).
[Maximum mark: 2]
19M.2.hl.TZ2.4d(ii)
Rhenium, Re, was the last element with a stable isotope to be isolated.
One chloride of rhenium has the empirical formula ReCl3.
(d(ii))
Calculate the percentage, by mass, of rhenium in ReCl3.
[2]
Markscheme
«Mr ReCl3 = 186.21 + (3 × 35.45) =» 292.56 [✔]
«100 × =» 63.648 «%» [✔]
Examiners report
Most candidates were able to answer this stoichiometric question correctly.
