Boiling point of chloroform was raised by 0.323 K, when 0.5143 g of anthracene was dissolved in 35 g of chloroform. Molecular mass of anthracene is (kf. for .C H C l3=3.9 K kg mol -1)

Question

Boiling point of chloroform was raised by 0.323 K, when 0.5143 g of anthracene was dissolved in 35 g of chloroform. Molecular mass of anthracene is (kf. for .C H C l3=3.9 K kg mol -1) (A) 79.42 g/mol (B) 132.32 g/mol (C) 177.42 g/mol (D) 242.32 g/mol

Tardigrade Admin · Accepted Answer

Here, elevation in boiling point, Δ Tb=0.323 K weight of anthracene, w=0.5143 g weight of chloroform W=35 g molal elevation constant kb=3.9 K kg / mol m=(kb × w × 1000/W × Δ Tb) =(3.9 × 0.5143 × 1000/0.323 × 35) =177.42 g / mol

Q. Boiling point of chloroform was raised by 0.323K, when 0.5143g of anthracene was dissolved in 35g of chloroform. Molecular mass of anthracene is (kf​ for CHCl3​=3.9Kkgmol−1)

79.42 g/mol

132.32 g/mol

177.42 g/mol

242.32 g/mol

Here, elevation in boiling point, ΔTb​=0.323K weight of anthracene, w=0.5143g weight of chloroform W=35g molal elevation constant kb​=3.9Kkg/mol m=W×ΔTb​kb​×w×1000​ =0.323×353.9×0.5143×1000​ =177.42g/mol

Q. Boiling point of chloroform was raised by $0.323 K$ , when $0.5143 g$ of anthracene was dissolved in $35 g$ of chloroform. Molecular mass of anthracene is $(k_{f}$ for $C H C l_{3} = 3.9 K k g m o l^{- 1})$