Does higher melting point mean lower freezing point?

[ieatshrimp24]

Just a quick question in case I need to spot trends. I understand more solute particles means higher melting point and lower freezing point. But does a compound's inherent melting point affect its freezing point?

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[theA1doctor]

Melting point and freezing point is the same thing.

 

[Cawolf]

I am assuming you meant a higher boiling point since you referred to solute.

Then you ask does the inherent boiling point effect the freezing point.

This is compound dependent and I don't think one point can be inferred from the other.

 

[azor ahai]

These are colligative properties. More solutes means more things to get in the way of creating lattice structures when freezing, so more energy is required. This explains freezing point depression. Boiling point elevation is explained by the greater amount of intermolecular forces in a solution which means more energy is required to break them to enter the gaseous phase. This difficulty to leave the liquid is also what explains vapor pressure depression.

You can see here that they are just inverses of each other. But here's a case where they aren't.

Among branched alkanes, increased branching raises the melting point (=freezing point), and lowers the boiling point. Yet compared to unbranched alkanes, increased branching lowers both.

 

[ieatshrimp24]

Yeah I meant boiling point. Thanks for the responses.