HARD

Earn 100

The vapour pressure of ${CS}_{2}$ at $50 ° C$ is $854$ torr and a solution of $2.0 gm$ sulphur in $100 gm$ of ${CS}_{2}$ has vapour pressure $848.9$ torr. If the formula of sulphur molecule is $S_{n},$ then calculate the value of $" n "$ (approx.) (At. mass of $S = 32$ ) :-

50% studentsanswered this correctly

Important Questions on Solutions

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

How many grams of glucose are required to prepare an aqueous solution of glucose having a vapor pressure of

23.324 mm Hg

25 ° C

100 g

of water? The vapour pressure of pure water at

25 ° C

23.8 mm Hg .

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

For a solution formed by mixing liquids

L

and

M

, the vapour pressure of

L

plotted against the mole fraction of

M

in solution is shown in the following figure, Here,

X_{L}

and

X_{M}

represent mole fractions of

L

and

M

, respectively, in the solution. The correct statement(s) applicable to this system is(are) -

Question Image

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

The vapour pressure of a solution of glucose is

720 mmHg

100^{o} C

. What is the mole fraction of water in this solution?

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

Benzene and toluene form nearly ideal solution. At

20 ° C

, the vapour pressure of benzene is

75 torr

and that of toluene is

22 torr

. The partial vapour pressure of benzene at

20 ° C

for a solution containing

78 g

of benzene and

46 g

of toluene (in

torr

) is

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

9 gram anhydrous oxalic acid (mol. Wt. = 90) was dissolved in 9.9 moles of water. If vapour pressure of pure water is

P_{1}^{o}

the vapour pressure of solution is

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

Which of the following statement is true?

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

38.4 g

of unknown substance (molar mass

384 g {mol}^{- 1}

) and

116 g

of acetone is used to prepare a solution at

313 K

. If vapour pressure of pure acetone (molar mass

58 g {mol}^{- 1}

) is

0.842

atmosphere, what is the vapour pressure of solution ?

HARD

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

104.2 ° C,

the vapour pressure of a solution of

7.5 g

of a solute in

100 g

of water is

740 mm

Hg

and

K_{b} = 0.55,

then the boiling point of the solution is ________

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

Two open beakers one containing a solvent and the other containing a mixture of that solvent with a non volatile solute are together sealed in a container. Over time:

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

Relative lowering of vapour pressure of a dilute solution of glucose dissolved in

1 kg

of water is

0.002

. The molality of the solution is

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

vapour pressure of water at

293 K

17535 mm Hg .

The vapour pressure of water at

293 K

containing

25 g

of glucose dissolved in

450 g

of water is

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

At room temperature, a dilute solution of urea is prepared by dissolving

0.60 g

of urea in

360 g

of water. If the vapour pressure of pure water at this temperature is

35 m m H g

, lowering of vapour pressure will be:
(molar mass of urea

= 60 g m o l^{- 1}

)

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

The vapour pressure of a solvent decreased by

20 mm

Hg

when a non-volatile solute was added to the solvent. The mole-fraction of the solute in the solution is

0.5

. What should be the mole-fraction of the solvent for the decrease in the vapour pressure needs to be

10 mm

Hg

HARD

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

The plot of total vapour pressure as a function of mole fraction of the components of an ideal solution formed by mixing liquids

X

and

Y

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

The vapor pressure of a dilute solution of glucose is

750 mm

of mercury at

373 K .

The mole fraction of the solute is _________

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

The solution having lowest vapour pressure amongst the following is

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

In which of the following lowering of vapour pressure would be maximum?

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

A set of solutions is prepared using

180 g

of water as a solvent and

10 g

of different non-volatile solutes

A, B

and

C

. The relative lowering of vapour pressure in the presence of these solutes are in the order [Given, molar mass of

A = 100 g {mol}^{- 1}; B = 200 g {mol}^{- 1}; C = 10, 000 g {mol}^{- 1}

]

MEDIUM

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

Liquid

M

and liquid

N

form an ideal solution. The vapour pressures of pure liquids

M

and

N

are

450

and

700 m m H g,

respectively, at the same temperature. Then correct statements is:
(

x_{M} = M o l e f r a c t i o n o f {' M}^{'} i n s o l u t i o n;

x_{N} = M o l e f r a c t i o n o f {' N}^{'} i n s o l u t i o n;

y_{M} = M o l e f r a c t i o n o f {' M}^{'} i n v a p o u r p h a s e;

y_{N} = M o l e f r a c t i o n o f {' N}^{'} i n v a p o u r p h a s e;

)

EASY

Chemistry>Physical Chemistry>Solutions>Lowering of Vapour Pressure

The mass of a non-volatile, non-electrolyte solute (molar mass

= 50 g {mol}^{- 1}

) needed to be dissolved in

114 g

octane to reduce its vapour pressure by

75 %

, is:

The vapour pressure of CS2 at 50°C is 854 torr and a solution of 2.0 gm sulphur in 100 gm of CS2 has vapour pressure 848.9 torr. If the formula of sulphur molecule is Sn, then calculate the value of "n" (approx.) (At. mass of S=32) :-

Important Questions on Solutions

Learn and Prepare for any exam you want !

The vapour pressure of ${CS}_{2}$ at $50 ° C$ is $854$ torr and a solution of $2.0 gm$ sulphur in $100 gm$ of ${CS}_{2}$ has vapour pressure $848.9$ torr. If the formula of sulphur molecule is $S_{n},$ then calculate the value of $" n "$ (approx.) (At. mass of $S = 32$ ) :-