when a solute is added to a solvent, the boiling point of the solution is higher

Question

when a solute is added to a solvent, the boiling point of the solution is higher than the pure solvent's was, but the melting point of it is lower. i know this is because the intermolecular forces are larger when it is boiling, and smaller when it is melting. i also know that it has something to do with the different forces between solute-solute, solvent-solvent, and solute-solvent. what i don't understand is why intermolecular forces can be strong at one point, yet weak at others. thanks for the help.

Explanation / Answer

In solids there exists lattice structures, so when solute is added, it disturbs the lattice structure. Thus the intermolecular forces are now weak , since in perfect lattice atoms are ordered and thus bonded strongly. When lattice is disturbed like some of atoms is lattice is replaced by solute , bonding decreases. hence less temeperature is required to melt those solids. In liquids when solute is added they take some surface area. thus vapour pressure increases ,hence more heat required to boil of the molecules,

Related Questions

Navigate

• Browse (All)
• Browse W
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.