DP Physics (first assessment 2025)

Question EXE.2.SL.TZ0.8c

Date	Example questions Example questions	Marks available	[Maximum mark: 2]	Reference code	EXE.2.SL.TZ0.8c
Level	SL	Paper	2	Time zone	TZ0
Command term	Outline	Question number	c	Adapted from	N/A

[Maximum mark: 2]

EXE.2.SL.TZ0.8c

(c)

The temperature of the sample is increased without a change in pressure. Outline the effect it has on the density of the gas.

[2]

Markscheme

ALTERNATIVE 1

The average translational speed increases «because T increases» ✓

From $P = \frac{1}{3} ρ v^{2}$ , the density decreases «to keep $P$ constant» ✓

ALTERNATIVE 2

From the ideal gas law, the volume of the gas increases ✓

Since $ρ = \frac{m}{v}$ and $m$ is constant, the density decreases ✓

Syllabus sections