Advertisements
Advertisements
प्रश्न
When 2.56 g of sulphur was dissolved in 100 g of CS2, the freezing point lowered by 0.383 K. Calculate the formula of sulphur (Sx).
(Kf for CS2 = 3.83 K kg mol−1, Atomic mass of sulphur = 32 g mol−1]
उत्तर
Given:
Kf = 3.83 K kg mol−1
Mass of solute = 2.56 g
Mass of solvent = 100 g
Therefore,
`"Molality of the solution, "m =2.56/32xx1000/100=0.8m`
The depression in freezing point of a solution is given as
∆Tf = iKfm
0.383= i×3.83×0.8
i = 1/8
Hence, 8 sulphur atoms are undergoing association, as shown below:
8 S ⇌ S8
APPEARS IN
संबंधित प्रश्न
A 5% solution (by mass) of cane sugar in water has freezing point of 271 K. Calculate the freezing point of 5% glucose in water if freezing point of pure water is 273.15 K.
Cryoscopic constant of a liquid is ____________.
Pure benzene freezes at 5.45°C. A 0.374 m solution of tetrachloroethane in benzene freezes at 3.55°C. The Kf for benzene is:
A solution containing 1.8 g of a compound (empirical formula CH2O) in 40 g of water is observed to freeze at –0.465° C. The molecular formula of the compound is (Kf of water = 1.86 kg K mol–1):
Which has the highest freezing point?
How does sprinkling of salt help in clearing the snow covered roads in hilly areas? Explain the phenomenon involved in the process.
Of the following four aqueous solutions, total number of those solutions whose freezing points is lower than that of 0.10 M C2H5OH is ______. (Integer answer)
- 0.10 M Ba3 (PO4)2
- 0.10 M Na2 SO4
- 0.10 M KCl
- 0.10 M Li3 PO4
Out of the following 1.0 M aqueous solution, which one will show the largest freezing point depression?
The depression in the freezing point of water observed for the same amount of acetic acid, trichloroacetic acid, and trifluoroacetic acid increases in the order given above. Explain briefly.
The of water observed for the same amount of acetic acid, trichloroacetic acid and trifluoroacetic acid increases in the order given above. Explain briefly.