Which of the following contains greatest number of oxygen atoms ? .

Options

A. 1g of O
B. 1g of O_(2)
C. g of `O_(3)`
D. all have the same number of atoms

Explanation

To determine which of the given options contains the greatest number of oxygen atoms, we need to analyze the number of moles of oxygen in each option based on their molar masses. Let's break down the steps:

### Step 1: Identify the Options
Assume the options are:
1. O (Oxygen)
2. O2 (Dioxygen)
3. O3 (Ozone)
4. H2O (Water)

### Step 2: Calculate Moles of Oxygen in Each Option
To find the number of oxygen atoms, we need to calculate the number of moles of oxygen in each compound. The formula for calculating moles is:
\[ n = \frac{\text{mass}}{\text{molar mass}} \]

#### Option 1: O (1 gram)
- Molar mass of O = 16 g/mol
- Moles of O = \( \frac{1 \text{ g}}{16 \text{ g/mol}} = 0.0625 \text{ moles} \)
- Number of oxygen atoms = \( 0.0625 \text{ moles} \times N_A \) (where \( N_A \) is Avogadro's number)

#### Option 2: O2 (1 gram)
- Molar mass of O2 = 32 g/mol
- Moles of O2 = \( \frac{1 \text{ g}}{32 \text{ g/mol}} = 0.03125 \text{ moles} \)
- Number of oxygen atoms = \( 0.03125 \text{ moles} \times 2 \times N_A = 0.0625 \times N_A \)

#### Option 3: O3 (1 gram)
- Molar mass of O3 = 48 g/mol
- Moles of O3 = \( \frac{1 \text{ g}}{48 \text{ g/mol}} = 0.02083 \text{ moles} \)
- Number of oxygen atoms = \( 0.02083 \text{ moles} \times 3 \times N_A = 0.0625 \times N_A \)

#### Option 4: H2O (1 gram)
- Molar mass of H2O = 18 g/mol
- Moles of H2O = \( \frac{1 \text{ g}}{18 \text{ g/mol}} = 0.05556 \text{ moles} \)
- Number of oxygen atoms = \( 0.05556 \text{ moles} \times 1 \times N_A = 0.05556 \times N_A \)

### Step 3: Compare the Number of Oxygen Atoms
Now we can compare the total number of oxygen atoms in each option:
- Option 1: \( 0.0625 \times N_A \)
- Option 2: \( 0.0625 \times N_A \)
- Option 3: \( 0.0625 \times N_A \)
- Option 4: \( 0.05556 \times N_A \)

### Conclusion
Options 1, 2, and 3 all contain the same number of oxygen atoms, which is greater than that in option 4 (H2O). Therefore, the correct answer is that options 1 (O), 2 (O2), and 3 (O3) contain the greatest number of oxygen atoms.

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