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Molality from molarity, density or percentage data

This type of question, asked 7 times: 2021 Paper 16, 27 Jul 2022, 1 Feb 2023, 29 Jan 2024, 6 Apr 2024, 9 Apr 2024, 22 Jan 2025. All 9 questions below, oldest first.

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  1. Question 1

    2021 Paper 16

    19
    If density of aqueous NaOHNaOH solution is 1.2 g/cm31.2\text{ }g/cm^{3}, then find its molality. [Given that: density of water =1gm/cm3= 1gm/cm^{3} and molar mass of NaOH=40gmNaOH = 40gm ]

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  2. Question 2

    27 Jul 2022

    31
    250 g250\text{ }g solution of DD-glucose in water contains 10.8%10.8\% of carbon by weight. The molality of the solution is nearest to (Given: Atomic Weights are H,1u;C,12u;O,16uH,1u;C,12u;O,16u )

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  3. Question 3

    1 Feb 2023

    58
    The density of 3M3M solution of NaClNaCl is 1.0 g mL−11.0\text{ }g{\text{ }mL}^{- 1}. Molality of the solution is ×10−2 m\times10^{- 2}\text{ }m. (Nearest integer). Given: Molar mass of NaNa and ClCl is 23 and 35.5 g mol−135.5\text{ }g{\text{ }mol}^{- 1} respectively.

  4. Question 4

    1 Feb 2023

    150
    The molality of a 10%(v/v)10\%(v/v) solution of di-bromine solution in CCl4CCl_{4} (carbon tetrachloride) is ' xx '. x=x =_______×10−2 m\times10^{- 2}\text{ }m. (Nearest integer) [Given: molar mass of Br2=160 g mol−1Br_{2}= 160\text{ }g{\text{ }mol}^{- 1}
     atomic mass of C=12 g mol−1 atomic mass of Cl=35.5 g mol−1 density of dibromine =3.2 g cm−3 density of  CCl4=1.6 g cm−3]\begin{matrix} & \text{~atomic mass of~}C = 12\text{ }g{\text{ }mol}^{- 1} \\ & \text{~atomic mass of~}Cl = 35.5\text{ }g{\text{ }mol}^{- 1} \\ & \text{~density of dibromine~}= 3.2\text{ }g{\text{ }cm}^{- 3} \\ & \text{~density of~}\left. \ CCl_{4}= 1.6\text{ }g{\text{ }cm}^{- 3} \right\rbrack \end{matrix}

  5. Question 5

    29 Jan 2024

    144
    Molality of 0.8MH2SO40.8MH_{2}SO_{4} solution (density 1.06 g cm−31.06\text{ }g{\text{ }cm}^{- 3} ) is ____ ×10−3 m\times10^{- 3}\text{ }m.

  6. Question 6

    6 Apr 2024

    122
    Molality (m) of 3M3M aqueous solution of NaClNaCl is: (Given : Density of solution =1.25 g mL−1= 1.25\text{ }g{\text{ }mL}^{- 1}, Molar mass in gmol−1:Na−23,Cl−35.5gmol^{- 1}:Na - 23,Cl - 35.5 )

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  7. Question 7

    6 Apr 2024

    46
    The density of ' xx ' M solution ('x' molar) of NaOHNaOH is 1.12 g mL−11.12\text{ }g{\text{ }mL}^{- 1}. while in molality, the concentration of the solution is 3 m3\text{ }m ( 3 molal). Then xx is (Given: Molar mass of NaOHNaOH is 40 g/mol40\text{ }g/mol )

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  8. Question 8

    9 Apr 2024

    56
    Molarity (M) of an aqueous solution containing xgxg of anhyd. CuSO4CuSO_{4} in 500 mL500\text{ }mL solution at 32 ∘C32\ ^{\circ}C is 2×10−1M2 \times10^{- 1}M. Its molality will be _____ ×10−3 m\times10^{- 3}\text{ }m. (nearest integer). [Given density of the solution =1.25 g/mL= 1.25\text{ }g/mL.]

  9. Question 9

    22 Jan 2025

    111
    Density of 3 M NaCl solution is 1.25 g/mL1.25\text{ }g/mL. The molality of the solution is :

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