What is the molar mass of water (H_2O) in a hydrate, expressed in g/mol?

• A. 2.02 g/mol
• B. 20.02 g/mol
• C. 16.00 g/mol
• D. 18.02 g/mol

Answer: (D)

Verified step by step guidance

1. Identify the chemical formula of water, which is H\_2O, meaning it contains 2 hydrogen atoms and 1 oxygen atom.
2. Find the atomic masses of hydrogen and oxygen from the periodic table: hydrogen is approximately 1.01 g/mol and oxygen is approximately 16.00 g/mol.
3. Calculate the total mass contributed by hydrogen atoms by multiplying the number of hydrogen atoms by the atomic mass of hydrogen: 2 \times 1.01 g/mol.
4. Add the mass of oxygen to the total hydrogen mass to get the molar mass of water: (2 \times 1.01) + 16.00 g/mol.
5. Sum these values to find the molar mass of water, which is the mass of one mole of H\_2O molecules expressed in g/mol.