Step 1: Determine the molar mass of water The molar mass of water (\( \text{H}_2\text{O} \)) is calculated by summing the atomic masses of its constituent elements:- Hydrogen (H) has an atomic mass of 1 g/mol.- Oxygen (O) has an atomic mass of 16 g/mol.The calculation for the molar mass of \( \text{H}_2\text{O} \) is as follows:\[M_{\text{H}_2\text{O}} = (2 \times 1 \, \text{g/mol}) + 16 \, \text{g/mol} = 18 \, \text{g/mol}\]Step 2: Apply the formula to compute the number of moles The relationship between mass, molar mass, and the number of moles (\( n \)) is defined by the formula:\[n = \frac{\text{Mass}}{\text{Molar mass}}\]Inserting the given values yields:\[n = \frac{18 \, \text{g}}{18 \, \text{g/mol}} = 1 \, \text{mol}\]Answer: Consequently, 18 g of water contains 1 mol. The correct option is (1).