JEE Main · 2023 · 24 Jan 2023 · Shift 2 · Some Basic Concepts of Chemistry

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The number of units, which are used to express concentration of solutions from the following is ____.
Mass percent, Mole, Mole fraction, Molarity, ppm, Molality.

Answer: 5

Solution

Concentration expresses how much solute is present relative to solvent or solution, and from the list mass percent, mole fraction, molarity, parts per million and molality all do this. The mole measures only an amount of substance and carries no reference to the quantity of solvent or solution, so it is not a concentration unit. Five of the listed quantities express concentration.

JEE Main · 2023 · 24 Jan 2023 · Shift 2 · Integer answer

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