What is the molar mass of Al_2(CO_3)_3?

• A. 180.03 g/mol
• B. 234.00 g/mol
• C. 197.96 g/mol
• D. 246.02 g/mol

Answer: (B)

Verified step by step guidance

1. Identify the chemical formula given: Al_2(CO_3)_3, which means the compound contains 2 aluminum (Al) atoms, 3 carbonate (CO_3) groups.
2. Determine the atomic masses of each element involved: Aluminum (Al) ≈ 26.98 g/mol, Carbon (C) ≈ 12.01 g/mol, Oxygen (O) ≈ 16.00 g/mol.
3. Calculate the total mass contributed by aluminum atoms: multiply the number of Al atoms by the atomic mass of Al, i.e., \$2 \times 26.98$ g/mol.
4. Calculate the total mass contributed by carbonate groups: first find the mass of one carbonate ion by adding the masses of 1 carbon and 3 oxygen atoms, i.e., \$12.01 + 3 \times 16.00$ g/mol, then multiply by 3 because there are three carbonate groups.
5. Add the total mass of aluminum and the total mass of carbonate groups to find the molar mass of Al_2(CO_3)_3: \(\text{Molar mass} = (2 \times 26.98) + 3 \times (12.01 + 3 \times 16.00)\) g/mol.