Question

Tolong bantuannya yaa,
3gr urea(Mr=60gr/mol) dan 3gram magnesium sulfat (Mr=120 gr/mol) dilarutkan dlm 50gr air. Tentukan titik didihnya! (Kb=0.5)

Answer 1

Gter1 = 3 gr, Mr = 60, gter2 = 3 gr, Mr = 120, gpel = 50 gr,  Kb = 0,5, Tb = ...
Keterangan, gter = gram terlarut, gpel = gram pelarut

ΔTb = Tb - Tb°
Tb° = 100°C
ΔTb = m.Kb
m(campuran) = (mol ter1 + mol ter2) . 1000/g pel

ΔTb = ΔTb
Tb - Tb° = m(campuran).Kb
Tb - 100 = (mol ter1 + mol ter2).1000/g pel . Kb
Tb- 100 = (3/60 + 3/120).1000/50 . 0.5
Tb - 100 = (0,05 + 0,025).20.0,5
Tb - 100 = 0,075.40
Tb - 100 = 3
Tb = 103°C