DP Chemistry (last assessment 2024)
Question 18M.2.sl.TZ1.a.i
| Date | May 2018 | Marks available | [Maximum mark: 2] | Reference code | 18M.2.sl.TZ1.a.i |
| Level | sl | Paper | 2 | Time zone | TZ1 |
| Command term | Calculate | Question number | a.i | Adapted from | N/A |
a.i.
[Maximum mark: 2]
18M.2.sl.TZ1.a.i
Urea, (H2N)2CO, is excreted by mammals and can be used as a fertilizer.
Calculate the percentage by mass of nitrogen in urea to two decimal places using section 6 of the data booklet.
[2]
Markscheme
molar mass of urea «= 4 × 1.01 + 2 × 14.01 + 12.01 + 16.00» = 60.07 «g mol–1»
«% nitrogen = × 100 =» 46.65 «%»
Award [2] for correct final answer.
Award [1 max] for final answer not to two decimal places.
[2 marks]
