Question

1a. Consider a compound with two solid phases, a low-pressure phase and a high-pressure phase(like carbon). Sketch the phase diagram for this compound, assuming that both solid phases are denser than its liquid phase. Identify all the important components of the diagram.

1b.For each option below, choose the one with a higher vapor pressure. Explain your answer please.

a)Methane vs Methanol. c) water at 20 degs C vs water at 80 degs C

b) ocatane vs hexane d) 10 mL of benzene vs 100 mLof benzene

Answer 1

Unfortunately i cannot answer your first question.

1b)

A) methane since alkanes have lower boiling point thus having higher vapour pressure bcz its easier for molecules to escape. Alcojols have h bonding which are strong forces and make it difficult to sepearte the molecules.

B) hexane since it has lower boiling point than octane. Lower bp is because boiling point increases with increasing chain lenght. Octane has greater molar mass than hexane. So low boiling point, higher vapor pressure.

C)water at 80degree C. Vapour pressure increases with increase in temperature.

D) both will have same v.p. vapour pressure is not affected by the volume of a liquid.