What is the mass of 9.45 mol of aluminum oxide (Al_2O_3)?

• A. 964 g
• B. 709 g
• C. 1120 g
• D. 254 g

Answer: (A)

Verified step by step guidance

1. Identify the chemical formula of aluminum oxide, which is \(\mathrm{Al_2O_3}\), meaning it contains 2 aluminum (Al) atoms and 3 oxygen (O) atoms per formula unit.
2. Calculate the molar mass of aluminum oxide by summing the atomic masses of its constituent atoms: use the atomic mass of aluminum (approximately 26.98 g/mol) and oxygen (approximately 16.00 g/mol). The molar mass is given by \$2 \times 26.98 + 3 \times 16.00$ g/mol.
3. Multiply the number of moles given (9.45 mol) by the molar mass of aluminum oxide to find the total mass. This uses the formula \(\text{mass} = \text{moles} \times \text{molar mass}\).
4. Set up the calculation explicitly as \$9.45 \, \mathrm{mol} \times \left(2 \times 26.98 + 3 \times 16.00\right) \, \mathrm{g/mol}$ to find the mass in grams.
5. Perform the multiplication to obtain the mass of aluminum oxide corresponding to 9.45 moles.