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Mole fraction from molality or mass percent

This type of question, asked 3 times: 8 Apr 2024, 22 Jan 2026 S2, 5 Apr 2026 S1. All 3 questions below, oldest first.

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  1. Question 1

    8 Apr 2024

    147
    Molality of an aqueous solution of urea is 4.44 m4.44\text{ }m. Mole fraction of urea in solution is x×10−3x\times10^{-3}. Value of xx is _______ . (integer answer)

  2. Question 2

    22 Jan 2026 S2

    26
    At T(K),100 gT(K),100\text{ }g of 98%H2SO4(w/w)98\%H_{2}SO_{4}(w/w) aqueous solution is mixed with 100 g of 49%H2SO4(w/w)49\%H_{2}SO_{4}(w/w) aqueous solution. What is the mole fraction of H2SO4H_{2}SO_{4} in the resultant solution? (Given : Atomic mass H=1u;S=32u;O=16uH = 1u;S = 32u;O = 16u ) (Assume that temperature after mixing remains constant)

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  3. Question 3

    5 Apr 2026 S1

    29
    What is the mole fraction of water in 10%10\% by weight (w/w)(w/w) of aqueous urea solution ? [Given : Molar mass of H,O,CH,O,C and N are 1, 16, 12 and 14 g mol−114\text{ }g{\text{ }mol}^{- 1} respectively]

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