Match List-I with List-II
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List-I: Concentration term |
List-II: Formula |
|
(A) Mass percentage |
(I) \( \frac{\text{Volume of solute}}{\text{Volume of solution}}\times100 \) |
|
(B) Volume percentage |
(II) \( \frac{\text{Moles of a component}}{\text{Total moles of all the components}} \) |
|
(C) Mole Fraction |
(III) \( \frac{\text{Moles of solute}}{\text{Mass of solvent in kg}} \) |
|
(D) Molality |
(IV) \( \frac{\text{Mass of solute}}{\text{Volume of solution}\times\text{Density of solution}}\times100 \) |
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 2
The correct answer is Option (2) → (A) - (IV), (B) - (I), (C) - (II), (D) - (III)
Each concentration term compares an amount of solute with an amount of solution or solvent. The definition of each term decides its formula.
(A) Mass percentage — This matches (IV) \(\frac{\text{Mass of solute}}{\text{Volume of solution}\times\text{Density of solution}}\times100\). Mass percentage is the mass of solute in 100 parts by mass of solution. Volume × density is the mass of the solution, so this formula is mass of solute/mass of solution × 100.
(B) Volume percentage — This matches (I) \(\frac{\text{Volume of solute}}{\text{Volume of solution}}\times100\). It is used for liquids: a 10% ethanol solution has 10 mL of ethanol in 100 mL of solution.
(C) Mole Fraction — This matches (II) \(\frac{\text{Moles of a component}}{\text{Total moles of all the components}}\). It is a ratio of moles, so it has no unit, and the mole fractions of all components add up to 1.
(D) Molality — This matches (III) \(\frac{\text{Moles of solute}}{\text{Mass of solvent in kg}}\). Molality uses the mass of the solvent, not of the solution, so it does not change with temperature.
Shortcut: (A)-(IV) appears only in Option (2).