Which of the following statements is(are) true?

a. LiF will have a higher vapor pressure at 25^οC than H₂S.

b. HF will have a lower vapor pressure at -50^οC than HBr.

c. Cl₂ will have a higher boiling point than Ar.

d. HCl is more soluble in water than in CCl₄.

e. MgO will have a higher vapor pressure at 25^οC than CH₃CH₂OH.