How does molar mass affect solubility?

1 Answer
Aug 7, 2017

Generally, higher molar mass compounds will be less soluble than lower molar mass molecules of the same type .


The comparison MUST be between compounds of similar types (alcohols, proteins, carbonates, etc.) because mass itself is not a major factor in whether a compound will dissolve in another one.

It also depends strongly on the solvent. Ionic compounds are less likely to dissolve in covalent solvents, and covalent compounds are less likely to dissolve in ionic compounds (including water). So, a higher-mass ionic compound (#CuCl_2# (MW 134) for example) would still be more soluble in water than hexane (MW 86), a covalent compound.