Question

Do ionic or covalent substances tend to produce more ions in solution?

Answer 1

it depends on the nature of the solvent
ionic cpound dissiociates to greater extent in polar solvent and covalent compound in non polar solvent

Answer 2

If we assume an aqueous (water) solvent, then this is a simple situation:\[C{_6}H{_1}{_2}O{_6}(s) \rightarrow C{_6}H{_1}{_2}O{_6}(aq)\] with no dissociation into ions\[NaCl(s) \rightarrow Na{^+}(aq) + Cl{^-}(aq)\] with LOTS of dissociation into ions. The exact formula of the salt may vary, but in general, ionic solutes produce more ions in solution than covalent solutes.