The number of atoms present in 1 g of hydrogen is the same as that in 1 g of oxygen.

Answer

To determine whether the number of atoms present in 1 g of hydrogen is the same as that in 1 g of oxygen, we will follow these steps:

### Step 1: Understand the concept of moles
The number of moles (n) can be calculated using the formula:
\[ n = \frac{\text{mass}}{\text{molar mass}} \]

### Step 2: Calculate the number of moles of oxygen (O2)
1. The molar mass of oxygen (O2) is 32 g/mol (since each oxygen atom has a molar mass of 16 g/mol, and there are two atoms in O2).
2. For 1 g of O2:
\[ n_{\text{O2}} = \frac{1 \text{ g}}{32 \text{ g/mol}} = \frac{1}{32} \text{ mol} \]

### Step 3: Calculate the number of atoms in 1 g of oxygen
1. To find the number of oxygen atoms, we multiply the number of moles by Avogadro's number (approximately \(6.022 \times 10^{23}\) atoms/mol):
\[ \text{Number of atoms in O2} = n_{\text{O2}} \times N_A = \frac{1}{32} \text{ mol} \times 6.022 \times 10^{23} \text{ atoms/mol} \approx 1.87 \times 10^{22} \text{ atoms} \]

### Step 4: Calculate the number of moles of hydrogen (H2)
1. The molar mass of hydrogen (H2) is 2 g/mol (since each hydrogen atom has a molar mass of 1 g/mol, and there are two atoms in H2).
2. For 1 g of H2:
\[ n_{\text{H2}} = \frac{1 \text{ g}}{2 \text{ g/mol}} = \frac{1}{2} \text{ mol} \]

### Step 5: Calculate the number of atoms in 1 g of hydrogen
1. To find the number of hydrogen atoms, we multiply the number of moles by Avogadro's number:
\[ \text{Number of atoms in H2} = n_{\text{H2}} \times N_A = \frac{1}{2} \text{ mol} \times 6.022 \times 10^{23} \text{ atoms/mol} \approx 3.01 \times 10^{23} \text{ atoms} \]

### Step 6: Compare the number of atoms
1. From the calculations:
- Number of atoms in 1 g of O2: \( \approx 1.87 \times 10^{22} \text{ atoms} \)
- Number of atoms in 1 g of H2: \( \approx 3.01 \times 10^{23} \text{ atoms} \)

### Conclusion
Since \(1.87 \times 10^{22} \neq 3.01 \times 10^{23}\), the statement that the number of atoms present in 1 g of hydrogen is the same as that in 1 g of oxygen is **false**.

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