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Model Paper 8 — Chemistry STD 11 Science — Question

Rajasthan BoardEnglish MediumSTD 11 ScienceChemistryModel Paper 81 Mark
MCQ
Assertion (A): Molarity of a solution represents its concentration.
Reason (R): Molarity is the number of moles of solute per litre of solution.
  • ✓
    Both A and R are true and R is the correct explanation of A.
  • B
    Both A and R are true but R is not the correct explanation of A.
  • C
    A is true but R is false.
  • D
    A is false but R is true.
✓

Answer

Correct option: A.
Both A and R are true and R is the correct explanation of A.
(a) Both A and R are true and R is the correct explanation of A .
Explanation: Concentration means how much amount of substance is present in a given volume of a solution. Now as amount can be measured in terms of moles, so molarity means concentration of the solution. According to Mole concept: 1 Mole of molecules $=$ Gram molecular mass $=6.023 \times 10^{23}$ molecules.

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