SolutionHard
Question
When 36.0 g of a solute having the empirical formula CH2O is dissolved in 1.20 kg of water, the solution freezes at −0.93°C. What is the molecular formula of the solute? (Kf = 1.86°C kg mol−1)
Options
A.C6H12O6
B.C3H6O3
C.CH2O
D.C2H4O2
Solution
$\Delta T_{f} = K_{f}.m \Rightarrow 0.93 = 1.86 \times \frac{36/M}{1.2} \Rightarrow M = 60$
If the molecular formula is CxH2xOx, then
12x + 2x + 16x = 60 ⇒ x = 2
∴ Molecular formula = C2H4O2
Create a free account to view solution
View Solution FreeMore Solution Questions
The vapour pressure of pure benzene at a certain temperature is 0.850 bar. A non-volatile non-electrolyte solid weighing...The pH vlues of aqueous solutions of which of the following compounds does not change on dilution ?...Which of the following is a buffer solution ?...The normal freezing point of nitrobenzene is 278.82 K. A non-volatile solute is dissolved in it and a solution of molali...The depression of freezing points of 0.05 molal aqueous solution of the following compounds are measured.1. NaCl 2. K2SO...