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.

2fe + 3h2so4 -> fe2(so4)3 + 3h2

it is necessary to balance equations in order to get the proper amount of reactants as well as products in order not to make a miscalculation.

you cannot change the subscripts as that would change the substance itself. for instance, diatomic elements such as h2 only have the subscript two when a gas. another example would be so4, if you were to change the subscript, the element would no longer be sulfate.

we change the coefficients instead as that only changes the number of molecules rather than the substance itself.

hope this !

14 days is the half-life of phosphorus-32