Which of these solutes raises the boiling point of water the most?
molecular sucrose (c12h22o11)
ionic sodium chloride (nacl)
ionic potassium bromide (kbr)
ionic calcium chloride (cacl2)
ionic aluminum fluoride (alf3)

This solute raises the boiling point of water the most, ionic aluminum fluoride (AlF3)

Explanation:

Boiling point elevation is one of the colligative properties. These are properties only for solutions and they depend on the  number of dissolved particles, the solute.

In the colligative properties you should take account the value of i, which means Van't Hoff factor and it represents degree of dissociation of solutes that are electrolytes.

Ths is the formula for boling point elevation:

ΔT = Kb · molality · i

ΔT = Tb (solution) - Tb (pure solvent)

Kb =  ebullioscopic constant

i = Van't Hoff factor

In sucrose, the i is 1 (non electrolyte)

NaCl ---> Na+  +  Cl- (the i is 2, you have 2 ions)

KBr ---> K+  +  Br-  (the same as NaCl)

CaCl2 > Ca2+  +  2Cl-  (the i is 3)

AlF3 > Al3+  +  3F-  (the i is 4)