How many moles of H_2O are present in 360 grams of water?

• A. 10 moles
• B. 20 moles
• C. 2 moles
• D. 18 moles

Answer: (A)

Verified step by step guidance

1. Identify the given information: the mass of water is 360 grams.
2. Recall the molar mass of water (H_2O). Calculate it by adding the atomic masses of hydrogen and oxygen: \(M_{H_2O} = 2 \times 1.008 + 15.999\) grams per mole.
3. Use the formula to find moles: \(\text{moles} = \frac{\text{mass}}{\text{molar mass}}\).
4. Substitute the known values into the formula: \(\text{moles of H_2O} = \frac{360}{M_{H_2O}}\).
5. Perform the division to find the number of moles of water in 360 grams.