CameraIcon

SearchIcon

MyQuestionIcon

1

You visited us 1 times! Enjoying our articles? Unlock Full Access!

Depression in Freezing Point

1.1 g CoCl3...

Question

1.1 g $C o C l_{3} \cdot 6 N H_{3}$ (Molar mass 267.5) was dissolved in 100 g of water. The freezing point of solution was $- {0.306}^{o} C$ . How many moles of solute particles exist in solution for each mole of solute introduced? $(K_{f}$ for $H_{2} O = 1.86 K m o l^{- 1} k g)$ .

Open in App

Solution

The molality of the solution is $m = \frac{\frac{1.1 g}{267.5 g / m o l}}{0.1 k g} = 0.04112 m o l / k g$ .
The expression for the depression in the freezing point is $Δ T_{f} = i K_{f} m$
Substitute values in the above expression.
$0.306 = i \times 1.86 \times 0.04112$
$i = 4$
Thus moles of solute particles exist in solution for each mole of solute introduced.

Suggest Corrections

thumbs-up

0

Similar questions

1.1 g C o C l_{x} \cdot y N H_{3}

(Molar mass 267.5) was dissolved in 100 g water. The solution shows freezing point

- {0.306}^{o} C

. How many solute particles exists in solution for each mole of solute introduced if 100% ionization of complex is noticed?

K_{f}

H_{2} O = 1.86 K m o l^{- 1} k g

. Also, find the value of

x

y

.

Q. An aqueous solution was found to have an osmotic pressure of 2.51 atm at

25^{o} C

. The freezing point of solution if

K_{f}

1.86 K m o l^{- 1} k g

Assume molarity and molality are same.

Q. Find the freezing point of a solution containing 0.5 mole of glucose dissolved in 200 g of

H_{2} O

K_{f}

for water is 1.86

K m^{- 1}

Q. (a) Define the following terms:
(i) Mole fraction
(ii) Ideal solution
(b) 15.0 g of an unknown molecular material was dissolved in 450 g of water. The resulting solution was found to freeze at

- {0.34}^{o} C

. What is the molar mass of this material? (

K_{f}

for water = 1.86 K kg mol

^{- 1}

Q. A certain mass of a substance, when dissolved in 100 g

C_{6} H_{6}

, lowers the freezing point by

{1.28}^{o} C

. The same mass of solute dissolved in 100 g water, lowers the freezing point by

{1.40}^{o} C

. If the substance has normal molar mass in benzene and is completely ionised in water, how many ions does it dissociate in water? (

K_{f}

H_{2} O

C_{6} H_{6}

are 1.86, 5.12 K

m o l^{- 1}

View More

Join BYJU'S Learning Program

similar_icon

Related Videos

lock

Depression in Freezing Point

CHEMISTRY

Watch in App

explore_more_icon

Explore more

Depression in Freezing Point

Standard XII Chemistry

Join BYJU'S Learning Program

CrossIcon