Can different substances have the same solubility curve? why or why not?

Different substances can not have the same solubility curve because the solute - solvent interaction between substances differ.

A solution is formed when a solute dissolves in a solvent. This interaction is unique from one substance to another. Each substance interacts differently with a solvent at different temperatures.

The solubility curve is a plot of solubility against temperature. Owing to the fact that different substances interact differently with different solvents at different temperatures, no two substances can have the same solubility curve.

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Yes, it's theoretically possible, but extremely unlikely.

The behaviour of solubility with temperature depends on several factors such as the attractive forces

•among the solute particles

•among the solvent particles

•between the solute and solvent particles

It is highly unlikely that all these forces would be the same for two different solutes.

Thus. different substances will almost certainly have different solubility curves

if you're asking what comes out, it's steam.