Question

Which of the substances in the table has the greatest number of particles in solution?

a.Sodium chloride
b.Potassium chloride
c.Calcium chloride
d.Sucrose

Answer 1

well, first of all consider that a molecular solid like sucrose does NOT dissociate into 'simpler' substances, merely the *inter*molecular bonds break. ionic solids like salts however DO dissociate (i.e. their *intra*molecular bonds break as well).

Answer 2

so immediately we disqualify sucrose. looking at our salts, however, consider their dissolution equations:$$NaCl\Leftrightarrow Na^++Cl^-\\KCl\Leftrightarrow K^++Cl^-\\CaCl_2\Leftrightarrow Ca^++2Cl^-$$so clearly calcium chloride dissociates into the most ions hence it has the greatest number of particles in solution