Density of 1 M solution of a non-electrolyte C6H12O6 is 1 18 g/mL If Kf(H2O) is1 86 mol - Chemistry - Solutions

Question

Density of 1 M solution of a non-electrolyte
C6H12O6 is 1 18 g/mL If
Kf(H2O) is1 86° mol–1
kg, solution freezes at -
(a) –1 58°C (b) –1 86°C (c) –3 16°C
(d) 1 86°C

Vartika Jain · Accepted Answer

Dear Student,

∆Tf=iKfmMolality, m=Molarity×1000density×1000-Molarity×Molar massMolar mass =6×12+12×1+2×6= 72+12+12=96 gmol-1m=1×10001
18×1000-1×96=10001180-96=10001084=0
922 mSInce the solute is non electrolyte, i=1Now, ∆Tf =1×1
86×0 922=1
71and, ∆Tf=Tf°-TfFor water,Tf°=0°CSo, 1
71=0°C-Tfor, Tf= -1
71°C Hence, the correct answer is (b)

Density of 1 M solution of a non-electrolyte C6H12O6 is 1.18 g/mL. If Kf(H2O) is1.86° mol–1 kg, solution freezes at - (a) –1.58°C (b) –1.86°C (c) –3.16°C (d) 1.86°C

Density of 1 M solution of a non-electrolyte C₆H₁₂O₆ is 1.18 g/mL. If K_f(H₂O) is1.86° mol^–1 kg, solution freezes at -
(a) –1.58°C (b) –1.86°C (c) –3.16°C (d) 1.86°C