Calculate the molar mass of aluminum oxide [tex]$\left( Al_2O_3 \right)$[/tex]. Express your answer to four significant figures.

The molar mass of [tex]$Al_2O_3$[/tex] is [tex]$\square$[/tex] grams.



Answer :

To calculate the molar mass of aluminum oxide [tex]\((\text{Al}_2\text{O}_3)\)[/tex], follow these steps:

1. Identify the atomic masses of aluminum (Al) and oxygen (O).
- The atomic mass of aluminum (Al) is 26.98 g/mol.
- The atomic mass of oxygen (O) is 16.00 g/mol.

2. Determine the number of atoms of each element in the chemical formula [tex]\(\text{Al}_2\text{O}_3\)[/tex]:
- There are 2 aluminum (Al) atoms.
- There are 3 oxygen (O) atoms.

3. Calculate the total mass contributed by the aluminum atoms:
- For aluminum: [tex]\(2 \text{ Al atoms} \times 26.98 \text{ g/mol} = 53.96 \text{ g/mol}\)[/tex]

4. Calculate the total mass contributed by the oxygen atoms:
- For oxygen: [tex]\(3 \text{ O atoms} \times 16.00 \text{ g/mol} = 48.00 \text{ g/mol}\)[/tex]

5. Add the masses of all the atoms to obtain the molar mass of aluminum oxide:
- Total molar mass = [tex]\(53.96 \text{ g/mol} + 48.00 \text{ g/mol} = 101.96 \text{ g/mol}\)[/tex]

Thus, the molar mass of aluminum oxide [tex]\((\text{Al}_2\text{O}_3)\)[/tex] is [tex]\(\boxed{101.96}\)[/tex] grams.