Answer:
The boiling point of the solution is 101,42ºC
Explanation:
Formula for boiling point elevation is:
ΔT = Kb · molality . i
Water boils at 100ºC, at 1 atm.
NiSO4 ----> Ni2+ + SO4-2 (assume 100% ionization, the value of i, is 2)
Tº boiling point solution - Tº boiling point = Ebulloscopic constant . molality . Van't Hoff factor.
Tº bp solution - 100ºC = 0,512 ºC/molal . molality . 2
Molality means moles of solute in 1kg of solvent (1000g)
Molar mass NiSO4 = 154,75 g/m
Mass/ Molar mass = Moles --> 21,6 g / 154,75 g/m = 0,139 moles
These moles are in 100 g of H2O, so we have to make a rule of three to find, the moles in 1000g
100 g _________0,139 moles
1000 g _______ 1,39 moles (molality)
Tº bp solution - 100ºC = 0,512 ºC/molal . 1,39molal . 2
Tº bp solution = (0,512 ºC/molal . 1,39molal . 2) + 100ºC
Tº bp solution = 101,42ºC
