solubility

What must occur for a substance to dissolve

bonds within the solute and solvent must break and bonds between the solute and solvent must form.

In general, when will a substance not dissolve

If the bonds to be broken are stronger than the bonds that will be formed.

Which solvents do ionic substances dissolve in and why

Polar solvents, because the ion-dipole bonds formed are strong enough.

Which solvents will ionic substances not dissolve in and why

Non-polar solvents, because the bonds between the ions are too strong for the non-polar molecules to pull them away from the ionic lattice.

Which solvents will covalent molecules dissolve in and why

Non-polar solvents, because the intermolecular bonds between covalent molecules are usually weak so can be broken by the non-polar solvent molecules.

Which solvents will covalent molecules not dissolve in

Polar solvents, because the intermolecular bonds between polar solvent molecules are too strong.

Ion-dipole bonds

• Form between ions and water molecules when an ionic substance is dissolved in water.

• The δ+ hydrogens are electrostatically attracted to the negative ions.

• The δ- oxygens are electrostatically attracted to the positive ions.

Hydration

When ions separate from an ionic lattice and become surrounded by water molecules. They are described as hydrated ions

When water is not the solvent, what is hydration called

Solvation