Q48.A solution containing 0.85 g of ZnCl2 in 125.0 g of water freezes at −0.23∘C. The apparent degree of dissociation of the salt is (Kf for water = 1.86 K kg mol−1 , atomic mass: Zn = 65.3 and Cl = 35.5) (1) 1.36% (2) 73.5% (3) 7.35% (4) 2.47%
What This Question Tests
This question involves calculating the degree of dissociation of an electrolyte using the colligative property of depression in freezing point, requiring calculation of molality and the Van't Hoff factor.
Concepts Tested
Formulas Used
ΔTf = i * Kf * m
m = moles of solute / kg of solvent
i = 1 + (n-1)α
📚 NCERT Sections This Tests
1.32 — Calculate The Depression In The Freezing Point Of Water When 10 G Of
Chemistry Class 11 · Chapter 1
1.32 Calculate the depression in the freezing point of water when 10 g of CH3CH2CHClCOOH is added to 250 g of water. Ka = 1.4 × 10–3, Kf = 1.86 K kg mol–1. 1.33 19.5 g of CH2FCOOH is dissolved in 500 g of water. The depression in the freezing point of water observed is 1.00 C. Calculate the van’t Hoff factor and dissociation constant of fluoroacetic acid.
1.34 — Vapour Pressure Of Water At 293 K Is 17.535 Mm Hg. Calculate The Vapour
Chemistry Class 11 · Chapter 1
1.34 Vapour pressure of water at 293 K is 17.535 mm Hg. Calculate the vapour pressure of water at 293 K when 25 g of glucose is dissolved in 450 g of water.
2.8 — The Conductivity Of 0.20 M Solution Of Kcl At 298 K Is 0.0248 S Cm–1. Calculate
Chemistry Class 11 · Chapter 2
2.8 The conductivity of 0.20 M solution of KCl at 298 K is 0.0248 S cm–1. Calculate its molar conductivity.
📋 Question Details
- Chapter
- Solutions
- Topic
- Colligative properties and dissociation
- Year
- 2012
- Shift
- 12 May Online
- Q Number
- Q48
- Type
- MCQ
- NCERT Ref
- Class 12 Chemistry Ch 2: Solutions
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