DP Chemistry (last assessment 2024)
Question 22M.2.sl.TZ1.1e(iii)
Date | May 2022 | Marks available | [Maximum mark: 1] | Reference code | 22M.2.sl.TZ1.1e(iii) |
Level | sl | Paper | 2 | Time zone | TZ1 |
Command term | Determine, Justify | Question number | e(iii) | Adapted from | N/A |
e(iii).
[Maximum mark: 1]
22M.2.sl.TZ1.1e(iii)
When heated in air, magnesium ribbon reacts with oxygen to form magnesium oxide.
Most nitride ions are 14N3–.
(e(iii))
The nitride ion and the magnesium ion are isoelectronic (they have the same electron configuration). Determine, giving a reason, which has the greater ionic radius.
[1]
Markscheme
nitride AND smaller nuclear charge/number of protons/atomic number ✔
Examiners report
In spite of being given the meaning of "isoelectronic", many candidates talked about the differing number of electrons and only about 30% could correctly analyse the situation in terms of nuclear charge.
