DP Physics (first assessment 2025)

Question SPM.2.SL.TZ0.6

Date	May Specimen-2023	Marks available	[Maximum mark: 5]	Reference code	SPM.2.SL.TZ0.6
Level	SL	Paper	2	Time zone	TZ0
Command term	Calculate, Suggest	Question number	6	Adapted from	N/A

[Maximum mark: 5]

SPM.2.SL.TZ0.6

Small pieces of solid paraffin with a total mass of 30 g at a temperature of 42 °C are mixed with 150 g of liquid paraffin at a temperature of 240 °C. The mixture is stirred until an equilibrium temperature is reached.

The following data for paraffin are available:

Specific heat capacity of solid paraffin = 0.7 kJ kg⁻¹ K⁻¹Specific heat capacity of liquid paraffin = 2.13 kJ kg⁻¹ K⁻¹Specific latent heat of fusion of paraffin = 220 kJ kg⁻¹Melting point of paraffin = 47 °C

(a)

Calculate the theoretical equilibrium temperature of the mixture.

[3]

Markscheme

$(0.030 \times 0.7 \times 10^{3} \times 5) + (0.030 \times 220 \times 10^{3}) + (0.030 \times 2.13 \times 10^{3}) (T - 47)$