DP Chemistry (last assessment 2024)
Question 22M.2.hl.TZ1.1d(iii)
Date | May 2022 | Marks available | [Maximum mark: 1] | Reference code | 22M.2.hl.TZ1.1d(iii) |
Level | hl | Paper | 2 | Time zone | TZ1 |
Command term | Determine | Question number | d(iii) | Adapted from | N/A |
d(iii).
[Maximum mark: 1]
22M.2.hl.TZ1.1d(iii)
When heated in air, magnesium ribbon reacts with oxygen to form magnesium oxide.
The presence of magnesium nitride can be demonstrated by adding water to the product. It is hydrolysed to form magnesium hydroxide and ammonia.
(d(iii))
Determine the oxidation state of nitrogen in Mg3N2 and in NH3.
[1]
Markscheme
Mg3N2: -3
AND
NH3: -3 ✔
Do not accept 3 or 3-
Examiners report
Good performance; however, surprising number of candidates could not determine one or both oxidation states correctly or wrote it as 3 or 3−, instead of −3.
