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 ?

Options

A. 4 g He
B. 46 g Na
C. 0.4 g Ca
D. 12 g He

Explanation

To determine which element contains the greatest number of atoms, we need to calculate the number of moles for each given option and then use Avogadro's number (approximately \(6.022 \times 10^{23}\) atoms per mole) to find the total number of atoms.

### Step-by-Step Solution:

1. **Identify the Molar Masses**:
- Helium (He): 4 g/mol
- Sodium (Na): 23 g/mol
- Calcium (Ca): 40 g/mol
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