DP Chemistry (last assessment 2024)
Question 19M.3.hl.TZ1.b(iv)
| Date | May 2019 | Marks available | [Maximum mark: 1] | Reference code | 19M.3.hl.TZ1.b(iv) |
| Level | hl | Paper | 3 | Time zone | TZ1 |
| Command term | Predict | Question number | b(iv) | Adapted from | N/A |
b(iv).
[Maximum mark: 1]
19M.3.hl.TZ1.b(iv)
Powdered zinc was reacted with 25.00 cm3 of 1.000 mol dm−3 copper(II) sulfate solution in an insulated beaker. Temperature was plotted against time.
Predict, giving a reason, how the final enthalpy of reaction calculated from this experiment would compare with the theoretical value.
[1]
Markscheme
lower/less exothermic/less negative AND heat loss/some heat not accounted for
OR
lower/less exothermic/less negative AND mass of reaction mixture greater than 25.00 g
OR
greater/more exothermic/more negative AND specific heat of solution less than water [✔]
Examiners report
Most scored a mark for predicting how the calculated enthalpy value would compare with the theoretical value.
