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MHT CET202526 Apr 2025Evening ShiftChemistrySome Basic Concepts of ChemistryActual

Calculate number of molecules present in 5.4 g of urea (Molar mass of urea =60 ~g ~mol ⁻¹ )

Options

  1. A6.022 10²²
  2. B5.419 10²²
  3. C4.312 10²²
  4. D9.933 10²²

Correct answer

B. 5.419 10²²

Step-by-step solution

The number of moles n is determined from the given mass and molar mass: n = 5.4 60 = 0.09 mol . Multiplying by Avogadro's number yields the number of molecules: 0.09 6.022 10²³ = 5.4198 10²² . Comparing with the options, the value 5.419 10²² corresponds to choice B .

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