DP Chemistry (last assessment 2024)
Question 21M.2.hl.TZ2.6
| Date | May 2021 | Marks available | [Maximum mark: 4] | Reference code | 21M.2.hl.TZ2.6 |
| Level | hl | Paper | 2 | Time zone | TZ2 |
| Command term | Determine | Question number | 6 | Adapted from | N/A |
6.
[Maximum mark: 4]
21M.2.hl.TZ2.6
Bromate and bromide ions react in acidic aqueous solution.
BrO3− (aq) + 5Br− (aq) + 6H+ (aq) → 3Br2 (l) + 3H2O (l)
The following rate data was collected.
(a)
Determine the rate expression for the reaction.
[2]
Markscheme
BrO3–: 1/first AND Br–: 1/first AND H+: 2/second ✓
«Rate =» k[BrO3−][Br−][H+]2 ✓
M2: Square brackets required for the mark.
(b)
Determine the value and unit of the rate constant using the rate expression in (a).
[2]
Markscheme
«k ==» 8.0 ✓
mol−3 dm9 s−1 ✓
