Number of moles of water present in 180 g of water will be:

Options

A. 5
B. 10
C. 15
D. 18

Explanation

To find the number of moles of water present in 180 g of water, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the formula for calculating moles**:
The number of moles (n) can be calculated using the formula:
\[ n = \frac{\text{Given mass}}{\text{Molar mass}} \]

2. **Determine the molar mass of water (H₂O)**:
- Water consists of 2 hydrogen (H) atoms and 1 oxygen (O) atom.
- The molar mass of hydrogen (H) is approximately 1 g/mol.
- Therefore, the total mass contributed by hydrogen in water is:
\[ 2 \times 1 \text{ g/mol} = 2 \text{ g/mol} \]
- The molar mass of oxygen (O) is approximately 16 g/mol.
- Thus, the total molar mass of water (H₂O) is:
\[ 2 \text{ g/mol} + 16 \text{ g/mol} = 18 \text{ g/mol} \]

3. **Use the given mass of water**:
- The given mass of water is 180 g.

4. **Calculate the number of moles**:
- Now, substitute the values into the moles formula:
\[ n = \frac{180 \text{ g}}{18 \text{ g/mol}} = 10 \text{ moles} \]

5. **Conclusion**:
- Therefore, the number of moles of water present in 180 g of water is **10 moles**.

### Final Answer:
The number of moles of water present in 180 g of water is **10 moles**.

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