Final answer:
The number of moles of Al(CN)3 in 221 g of the compound is approximately 2.10 moles, calculated using the molar mass of Al(CN)3 which is 105.04 g/mol.
Step-by-step explanation:
To calculate the number of moles of Al(CN)3 in 221 g of the compound, we need to know the molar mass of Al(CN)3. Each molecule of Al(CN)3 contains one aluminum atom (Al) and three cyanide groups (CN). The atomic mass of aluminum (Al) is approximately 26.98 g/mol, and the atomic mass of a cyanide group (CN) is about 26.02 g/mol (12.01 for carbon and 14.01 for nitrogen). Therefore, the molar mass of one mole of Al(CN)3 is 26.98 g/mol for Al + (3 × 26.02 g/mol for CN) = 105.04 g/mol for Al(CN)3.
Using this molar mass, we can set up a conversion from grams to moles:
- Divide the mass of Al(CN)3 by its molar mass: 221 g / 105.04 g/mol.
- This calculation gives us the number of moles: 221 g / 105.04 g/mol ≈ 2.10 moles of Al(CN)3.