Q44.The freezing point of benzene decreases by 0.45°C on adding 0 . 2 g of acetic acid to 20 g of benzene. If acetic acid associates to form a dimer in benzene, then what is the percentage association of acetic acid in benzene? Kf for benzene = 5 .12 K kg mol-1 (1) 80 . 4% (2) 74 . 6% (3) 94 . 6% (4) 64 . 6%
What This Question Tests
This complex numerical question combines freezing point depression with the concept of association, requiring the calculation of the Van't Hoff factor and then the percentage of association for acetic acid.
Concepts Tested
Formulas Used
ΔTf = i * Kf * m
i = (1 + (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.
1.31 — The Depression In Freezing Point Of Water Observed For The Same Amount Of
Chemistry Class 11 · Chapter 1
1.31 The depression in 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.
1.35 — Henry’S Law Constant For The Molality Of Methane In Benzene At 298 K Is
Chemistry Class 11 · Chapter 1
1.35 Henry’s law constant for the molality of methane in benzene at 298 K is 4.27 × 105 mm Hg. Calculate the solubility of methane in benzene at 298 K under 760 mm Hg.
📋 Question Details
- Chapter
- Solutions
- Topic
- Colligative properties
- Year
- 2017
- Shift
- 02 Apr
- Q Number
- Q44
- Type
- MCQ
- NCERT Ref
- Class 12 Chemistry Ch 2: Solutions
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