Choose the aqueous solution below with the highest boiling point. These are all solutions of nonvolatile solutes and you should assume ideal van't Hoff factors where applicable. A) 0.075 m NaI
B) 0.075 m (NH4)3PO4
C) 0.075 m NaBrO4
D) 0.075 m LiCN
E) 0.075 m KNO2

B. (NH₄)₃PO₄

Explanation:

Elevation of boiling point is one of the colligative properties.

Formula is: ΔT = Kb . m . i

ΔT = Boiling T° of solution - Boiling T° of pure solvent.

i = Van't Hoff factor (numbers of ions dissolved)

Kb = Ebulloscopic constant

In this case, all the m are the same so let's dissociate the salts:

NaI → Na⁺  +  I⁻     i = 2

(NH₄)₃PO₄ → 3NH₄⁺  +  PO₄⁻³     i = 4

NaBrO₄  →  Na⁺  +  BrO₄⁻    i = 2

LiCN  →  Li⁺  +  CN⁻         i = 2

KNO2  →  K⁺  +  NO₂⁻        i = 2

The biggest i would have the biggest boiling point, then B is the right answer, ammonium phosphate.

You count the i, with the moles of ions, you dissociate from the salt.

each  column  of the  table  is called a group. elements in a group share similar properties. groups are  read  from  top  to  bottom. metal. metalloid. nonmetal. solid. liquid. gas. fe. hg. o.  2. 3. 4. 5. 6. 7. 8. 9.  2. beryllium. 9.012. 4.  sodium. 22.990.  11. 3.  magnesium. 24.305.  12.  potassium. 39.098.  19. 4.  calcium. 40.078.  20. i guess  i