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Freezing or boiling point of a solution from its composition

This type of question, asked 9 times: 3 May 2023 S2, 10 May 2024 S1, 11 May 2024 S1, 14 May 2024 S1, 21 Apr 2025 S2, 16 Apr 2026 S1, 20 Apr 2026 S1, 12 May 2026 S2, 15 May 2026 S2. All 10 questions below, oldest first.

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  1. Question 1

    3 May 2023 S2

    51
    The molal elevation boiling point constant for water is 0.513∘C kg mol−10.513^{\circ}\text{C kg mol}^{-1}. Calculate boiling point of solution if 0.1 mole of sugar is dissolved in 200 g water?

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  2. Question 2

    10 May 2024 S1

    53
    3.2 g solute (molar mass 128 g/mol) in 80 g solvent, Kf=4.8K_f=4.8 K·kg/mol. Depression in freezing point is

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  3. Question 3

    11 May 2024 S1

    54
    If KbK_b denotes molal elevation constant of water, then boiling point of an aqueous solution containing 36 g glucose (molar mass = 180) per dm3^3 is:

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  4. Question 4

    14 May 2024 S1

    67
    Calculate the depression in freezing point of solution when 4 g nonvolatile solute of molar mass 126 g mol−1126\,\text{g mol}^{-1} is dissolved in 80 ml water. [Cryoscopic constant of water =1.86 K kg mol−1=1.86\,\text{K kg mol}^{-1}]

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  5. Question 5

    21 Apr 2025 S2

    63
    Calculate the boiling point elevation of solution if 15 g urea is dissolved in 1000 g water. [Kb\left\lbrack K_{b} \right. for water =0.52 K kg mol−1= 0.52\text{ }K\text{ }kg{\text{ }mol}^{- 1}; molar mass of urea =60 g mol−1= 60\text{ }g{\text{ }mol}^{- 1} ]

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  6. Question 6

    16 Apr 2026 S1

    25
    Calculate the boiling point of an aqueous solution containing 18 g glucose in 100 g water if the molal elevation constant of water is 0.5 K kg mol−1\mathrm{mol^{-1}}. [Molar mass of glucose =180= 180 g mol−1\mathrm{mol^{-1}} and boiling point of water =100 ∘C= 100\ ^\circ\mathrm{C}]

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  7. Question 7

    20 Apr 2026 S1

    23
    Calculate ΔTb\Delta T_b of a 0.450.45 m solution of a nonvolatile solute in solvent if molal elevation constant of solvent is 3.0 K kg mol−13.0\ \mathrm{K\,kg\,mol^{-1}}

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  8. Question 8

    12 May 2026 S2

    24
    Calculate the freezing point of a 0.050.05 m aqueous solution of a non-electrolyte at 298298 K. (Kf=1.86K_f = 1.86 K kg mol−1^{-1})

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  9. Question 9

    12 May 2026 S2

    23
    Calculate the boiling point of solution prepared by adding 2.932.93 g of solute to 0.0590.059 kg of solvent, if the boiling point of pure solvent = 61.2∘C61.2^\circ C, Kb=3.85∘CK_b = 3.85^\circ C Kg mol−1^{-1} and molar mass of solute =32= 32 g/mol)

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  10. Question 10

    15 May 2026 S2

    21
    Calculate the boiling point elevation of an aqueous solution containing 0.50.5 g glucose in 2020 g water if KbK_b for water is 0.52 K kg mol−10.52\ \mathrm{K\ kg\ mol^{-1}}. [Molar mass of glucose =180 g mol−1= 180\ \mathrm{g\ mol^{-1}}]

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