SOLUBILITY RULES!! (nitrates) :-)

Question

Chem homework help.. why are nitrates always soluble?

Also, what makes carbonates more likely to produce a salt in a reaction, compared to nitrates?

thanks a bunch :-)

Answer 1

The nitrate anion has three equivalent Oxygens surrounding a central Nitrogen atom.  This tends to spread the single negative charge and make it easier for water (using hydrogen bonds) to separate the ions in solution.

The carbonate anions have more localized charges (there are two for carbonate) and these have less resonance (the structure is more stable).  This means that the water will have a harder time separating the ions.

This assumes that the cations (positive part of the salt) are metal ions.  The tighter the ions are held, the less soluble the compound.