Question

Balance the following the chemical equation:

Al + O2 → Al2O3

Answer 1

To balance the chemical equation \( \text{Al} + \text{O}_2 \rightarrow \text{Al}_2\text{O}_3 \), we need to ensure that the number of each type of atom is the same on both sides of the equation.

1. **Count the atoms:**
- On the left side, we have:
- Aluminum (Al): 1
- Oxygen (O): 2
- On the right side, we have:
- Aluminum (Al): 2
- Oxygen (O): 3

2. **Balance aluminum (Al):**
- Since there are 2 Al atoms in \( \text{Al}_2\text{O}_3 \), we need 2 Al atoms on the left side. So, we put a coefficient of 2 in front of Al:
\[
2\text{Al} + \text{O}_2 \rightarrow \text{Al}_2\text{O}_3
\]

3. **Count the atoms again:**
- Left side:
- Al: 2
- O: 2
- Right side:
- Al: 2
- O: 3

4. **Balance oxygen (O):**
- To balance the oxygen, we need to adjust the amount of \( \text{O}_2 \). Since \( \text{Al}_2\text{O}_3 \) has 3 O atoms, we need \( \frac{3}{2} \) \( \text{O}_2 \) on the left. However, to avoid fractional coefficients, we multiply the entire equation by 2:
\[
4\text{Al} + 3\text{O}_2 \rightarrow 2\text{Al}_2\text{O}_3
\]

5. **Final count:**
- Left side:
- Al: 4
- O: 6 (3 \( \text{O}_2 \))
- Right side:
- Al: 4 (2 \( \text{Al}_2\text{O}_3 \))
- O: 6 (2 * 3 from \( \text{Al}_2\text{O}_3 \))

The balanced equation is:
\[
4\text{Al} + 3\text{O}_2 \rightarrow 2\text{Al}_2\text{O}_3
\]