Answer (Detailed Solution Below)

Option 2 : 13
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The correct answer is 13.

Concept:

  • Mole: One mole is the amount of a substance that contains as many particles or entities as there are atoms in exactly 12 g (or 0.012 kg) of the 12C isotope.

Calculation:

  • The number of moles in 52 g of He is 1
  • \(Number~of~ moles = {Mass~ of~ substance \over Mass~ of~ one ~mole}\)
  • The molar mass of helium gas is 4g/mol.
  • Given the number of moles of substance=52g
  • \(Number of moles = {52 \over 4}\)

The number of moles= 13g.

Hence the moles present in the 52g of He are 13Additional Information

  • Helium:
    • It is a noble gas.
    • It is used for filling balloons and other lighter aircraft.
    • Helium (He), when mixed with O2, is used by deep-sea divers for breathing and for respiratory patients.
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