DP Physics (first assessment 2025)

Question EXE.2.SL.TZ0.9b

Date	Example questions Example questions	Marks available	[Maximum mark: 4]	Reference code	EXE.2.SL.TZ0.9b
Level	SL	Paper	2	Time zone	TZ0
Command term	Calculate	Question number	b	Adapted from	N/A

[Maximum mark: 4]

EXE.2.SL.TZ0.9b

(b)

A container holds a mixture of argon and helium atoms at a temperature of 37 °C.

Calculate the average translational speed of the argon atoms.

The molar mass of argon is 4.0 × 10⁻² kg mol⁻¹.

[4]

Markscheme

Use of $\frac{4.0 \times 10^{- 2}}{N_{A}} (= 6.6 \times 10^{- 26} kg)$ ✓

Work showing that $v (= \sqrt{\frac{3 p}{ρ} = \sqrt{\frac{3 p V}{m}}}) = \sqrt{\frac{3 k T}{m}}$ ✓

Correct substitution AND conversion to K (310 K) ✓

430/440 «m s⁻¹» ✓

Syllabus sections