Chemistry · Oct / Nov 2023 · Paper 11 · Question 2

Data about two compounds is given. Both compounds have a simple molecular structure. | compound | melting point / °C | boiling point / °C | |---|---|---| | H₂S | –85 | –61 | | PCl₃ | –112 | 76 | Two bottles are placed, close together, inside a large container at a temperature of 90 °C. One bottle contains 1.0 g of H₂S, the other bottle contains 1.0 g of PCl₃. A detector is placed in the container 2.0 m away from the two bottles. The two bottles are opened at the same time. Which row is correct?

1. AH₂S; gases diffuse faster than liquids
2. BH₂S; H₂S has a lower Mᵣ than PCl₃
3. CPCl₃; gases diffuse faster than liquids
4. DPCl₃; PCl₃ has a lower Mᵣ than H₂S

As printed in the paper