How many moles of water are contained in 1.99 × 10^{26} molecules of water?

• A. 6.0 × 10^{24} moles
• B. 1.2 × 10^{3} moles
• C. 12 moles
• D. 330 moles

Answer: (D)

Verified step by step guidance

1. Identify the given quantity: the number of water molecules is \$1.99 \times 10^{26}$ molecules.
2. Recall Avogadro's number, which is the number of molecules in one mole: \$6.022 \times 10^{23}$ molecules/mole.
3. Set up the conversion from molecules to moles using the relationship: \(\text{moles} = \frac{\text{number of molecules}}{\text{Avogadro's number}}\).
4. Substitute the values into the formula: \(\text{moles} = \frac{1.99 \times 10^{26}}{6.022 \times 10^{23}}\).
5. Perform the division to find the number of moles of water molecules.