The number of atoms present in one mole of an element is equal to Avogadro number. Which of the following elements contains the greatest number of atoms ?A. `4" g He"`B. 46 g NaC. `0.4` g CaD. 12 g He

The number of atoms present in one mole of an element is equal to Avog

1.	The number of atoms present in one mole of an element is equal to Avogadro number. Which of the following elements contains the greatest number of atoms ?A. `4" g He"`B. 46 g NaC. `0.4` g CaD. 12 g He
Answer» Correct Answer - D For comparing number of atoms, first we calculate the moles as all are monoatomic and hence, Number of moles `=("Mass")/("Atomic mass")` Moles of 4 g He `=4/4 = 1` mol 46 g Na `=46/23 =2` mol `0.40` g Ca `=(0.40)/40=0.01` mol 12 g He `= 12/4=3` mol Now, number of atoms `="moles"xx"N"_("A")` Therefore, number of atoms are highest in 12 g He as it has the Masimum number of moles.

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