Here's how to determine the number of atoms in 2Al₂O₃:

1. Understand the Chemical Formula:

* Al₂O₃ represents one molecule of aluminum oxide.

* 2Al₂O₃ indicates two molecules of aluminum oxide.

2. Count the Atoms per Molecule:

* Each molecule of Al₂O₃ contains:

* 2 aluminum atoms (Al)

* 3 oxygen atoms (O)

3. Calculate the Total Atoms:

* Since we have two molecules of Al₂O₃, we multiply the atoms per molecule by 2:

* Aluminum atoms: 2 Al atoms/molecule * 2 molecules = 4 Al atoms

* Oxygen atoms: 3 O atoms/molecule * 2 molecules = 6 O atoms

4. Total Atoms:

* In 2Al₂O₃, there are a total of 4 + 6 = 10 atoms.