tentukan titik didih dan titik beku. natrium klorida 11,7 gram yang dilarutkan dalam 720 air

wt = 11,7 gram
Mr = 58 gram/mol
wp = 720 gram
kb = 0,52°C
kf = 1,86°C
Tb = ........................?
Tf = .........................?

m = wt/Mr x 1000/wp
= 11,7/58 x 1000/270
= 0,20 x 3,70
= 0,74 molal

ΔTb = m x Kb
= 0,74 x 0,52
= 0,38°C

Tb = Tb° + ΔTb
= 100 + 0,38
= 100,38°C

ΔTf = m x Kf
= 0,74 x 1,86
= 1,38°C

Tf = Tf° - ΔTf
= 0 - 1,38
= - 1,38°C