Assuming complete ionization- calculate freezing point of solton prepared by adding glaubers salt Na2SO4-10H20 in 0-1 kg of water - Kf - 1-86 k kg - mol Answer 271-95

The correct answer should be 271.96 K. The complete reaction will be according to the equation Na₂SO₄ → 2Na⁺ + SO₄ So, three particles have been formed ...

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

Byju's Answer

Standard XII

Chemistry

Molality

Assuming comp...

Question

Assuming complete ionization, calculate freezing point of solution prepared by adding 6g Glauber's salt ${N a}_{2} S O_{4} .10 H_{2} O$ in 0.1 kg of water ?(Given $K_{f}$ = 1.86 K kg/mol , Atomic masses, $N a = 23, O = 16, S = 32, H = 1$ )

Open in App

Solution

Step 1:

The chemical equation for the given reaction is as follows:

${N a}_{2} S O_{4} ⟶ 2 {N a}^{+} + S O_{4}^{2 -}$

So, three particles have been formed after complete dissociation.
The molar mass of Na₂SO₄.10H₂O will be = 46 + 32 + 64 + (10 x 18) = 322
Step 2:
The weight of water $W_{a}$ = 0.1 kg = 100 g

The weight of the solute (Glauber's salt) $W_{b}$ = 6.0 g

Given that, $K_{f}$ = 1.86 K kg mol⁻¹

i (Van't Hoff factor) = 3
Step 3:

According to the relation, $D T_{f} = \frac{K_{f}}{M B} \times \frac{W_{a}}{W_{b}} \times 1000 \times i$

= $\frac{1.86}{322} \times \frac{6.0}{100} \times 1000 \times 3$ = 1.039 K

So, the freezing point will be calculated as = 273 - 1.039 K = 271.96 K

Suggest Corrections

Similar questions

Q. Calculate the amount of

C a C l_{2}

(molar mass

= 111 g m o l^{- 1})

which must be added to 500 g of water to lower its freezing point by 2K, assuming

C a C l_{2}

is completely dissociated.

(K_{f}

for water

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

Q. Calculate the amount of

C a C l_{2}

(molar mass = 111g/mol) which must be added to 580g of water so that freezing point lower by 2K, assuming

C a C l_{2}

is completely dissociated:

[

K_{f}

for water = 1.86 K kg/mol].

Calculate the freezing point of a solution when 31 gram of Ethylene glycol is dissolved in 500 gram of water. (

Kf for water=1.86 k kg /mol

Q. One molal aqueous solution of

P d C l_{4} . 6 H_{2} O

has a freezing point 269.28 K. Assuming 100% ionization of complex, calculate the molecular formula of the complex. [

K_{f}

for water = 1.86 K kg mol

^{- 1}

]. The salt is a hydrated complex.

Calculate the normal freezing point of a sample of sea water containing 3.8 % nacl and 0.12 % of mgcl2 by mass given kf = 1.86 K kg/ mol molar mass of nacl 58.5 and mgcl2 95 g/mol

Join BYJU'S Learning Program

Assuming complete ionization, calculate freezing point of solution prepared by adding 6g Glauber's salt Na2SO4.10H2O in 0.1 kg of water ?(Given Kf = 1.86 K kg/mol , Atomic masses, Na=23,O=16,S=32,H=1 )

Assuming complete ionization, calculate freezing point of solution prepared by adding 6g Glauber's salt ${N a}_{2} S O_{4} .10 H_{2} O$ in 0.1 kg of water ?(Given $K_{f}$ = 1.86 K kg/mol , Atomic masses, $N a = 23, O = 16, S = 32, H = 1$ )