Depression in freezing point is 6 K for NaCl solution. If Kf for water is 1.86 K/kg mol, amount of NaCl dissolved in 1 kg water is:

Question

Depression in freezing point is 6 K for NaCl solution. If Kf for water is 1.86 K/kg mol, amount of NaCl dissolved in 1 kg water is: (A) 3.42 (B) 1.62 (C) 3.24 (D) 1.71

Tardigrade Admin · Accepted Answer

Δ Tf=i × Kf × (n/W) × 1000 i= vant Hoff factor Kf=1.86 K / kg mol n = number of moles W = weight of solvent =1 kg =1000 g Δ Tf=6 K so, 6=2 × 1.86 × (n/1000) × 10006 =2=1.86 × n n=(6/1.86)=1.62

Q. Depression in freezing point is 6K for NaCl solution. If Kf​ for water is 1.86K/kgmol, amount of NaCl dissolved in 1kg water is:

3.42

1.62

3.24

1.71

ΔTf​=i×Kf​×Wn​×1000 i= vant Hoff factor Kf​=1.86K/kgmol n= number of moles W= weight of solvent =1kg=1000g ΔTf​=6K so, 6=2×1.86×1000n​×10006 =2=1.86×n n=1.866​=1.62

Q. Depression in freezing point is $6 K$ for $N a Cl$ solution. If $K_{f}$ for water is $1.86 K / k g m o l$ , amount of $N a Cl$ dissolved in $1 k g$ water is: