DP Chemistry (last assessment 2024)
Question 22N.2.hl.TZ0.f.ii
| Date | November 2022 | Marks available | [Maximum mark: 2] | Reference code | 22N.2.hl.TZ0.f.ii |
| Level | hl | Paper | 2 | Time zone | TZ0 |
| Command term | Calculate | Question number | f.ii | Adapted from | N/A |
f.ii.
[Maximum mark: 2]
22N.2.hl.TZ0.f.ii
Ammonium nitrate, NH4NO3, is used as a high nitrogen fertilizer.
Solid ammonium nitrate can decompose to gaseous dinitrogen monoxide and liquid water.
Calculate the volume of dinitrogen monoxide produced at STP when a 5.00 g sample of ammonium nitrate decomposes. Use section 2 of the data booklet.
[2]
Markscheme
«5.00 g ÷ 80.06 g mol−1 =» 0.0625 mol «NH4NO3» ✔
«1:1 mol ratio»
«» 1.42 «dm3» ✔
Award [2] for correct final answer.
Accept range 1.36 – 1.43 «dm3».
Accept calculations based on PV=nRT.
Examiners report
Over three quarters of the candidates managed this straightforward gas volume calculation, with an approximately equal split between those using the molar volume and the ideal gas law.
