How many grams are present in 3.7 moles of Na2O?

• A. 62.9 g
• B. 74.0 g
• C. 142.6 g
• D. 229.4 g

Answer: (C)

Verified step by step guidance

1. Identify the chemical formula of the compound, which is sodium oxide, Na\_2O.
2. Calculate the molar mass of Na\_2O by adding the atomic masses of its elements: 2 sodium (Na) atoms and 1 oxygen (O) atom. Use the atomic masses from the periodic table (approximately 22.99 g/mol for Na and 16.00 g/mol for O). The molar mass is calculated as \$2 \times 22.99 + 16.00$ g/mol.
3. Use the formula to convert moles to grams: \(\text{mass (g)} = \text{moles} \times \text{molar mass (g/mol)}\).
4. Substitute the given number of moles (3.7 moles) and the molar mass you calculated into the formula: \(\text{mass} = 3.7 \times \text{molar mass}\).
5. Perform the multiplication to find the mass in grams, which will give you the amount of Na\_2O present in 3.7 moles.