DP Chemistry (last assessment 2024)

Test builder »

Question 19M.2.hl.TZ1.4b(iii)

Select a Test
Date May 2019 Marks available [Maximum mark: 2] Reference code 19M.2.hl.TZ1.4b(iii)
Level hl Paper 2 Time zone TZ1
Command term Sketch Question number b(iii) Adapted from N/A
b(iii).
[Maximum mark: 2]
19M.2.hl.TZ1.4b(iii)

This question is about the decomposition of hydrogen peroxide.

Hydrogen peroxide decomposes to water and oxygen when a catalyst such as potassium iodide, KI, is added.


2H2O2 (aq)  → KI (aq) O2 (g) + 2H2O (l)

(b(iii))

Additional experiments were carried out at an elevated temperature. On the axes below, sketch Maxwell–Boltzmann energy distribution curves at two temperatures T1 and T2, where T2 > T1.

[2]

Markscheme

peak of T2 to right of AND lower than T1     [✔]

lines begin at origin AND T2 must finish above T1     [✔]

Examiners report

Fair performance; errors including not starting the two curves at the origin, drawing peak for T2 above T1, T2 finishing below T1 or curves crossing the x-axis.

Syllabus sections