Question

Balance the following equation:
CaO+P2O5 = Ca3(PO4)2
Select the coefficient that would go in front of Ca3(PO4)2

Answer 1

To balance the equation:

1. Start with the unbalanced equation:
\[
\text{CaO} + \text{P}_2\text{O}_5 \rightarrow \text{Ca}_3(\text{PO}_4)_2
\]

2. Count the number of each type of atom on both sides of the equation:
- For \(\text{Ca}_3(\text{PO}_4)_2\):
- Calcium (Ca): 3
- Phosphorus (P): 2
- Oxygen (O): 8 (4 from PO4 * 2)

3. We need 3 calcium (Ca) from CaO, which leads to:
\[
3 \text{CaO}
\]
This gives us 3 calcium.

4. Now we consider phosphorus (P). We have 2 phosphorus in \(\text{Ca}_3(\text{PO}_4)_2\) and need one \(\text{P}_2\text{O}_5\):
\[
1 \text{P}_2\text{O}_5
\]

5. Now, let's check the balance of oxygen. We have:
- From \(3 \text{CaO}\): \(3 \times 1 = 3\) oxygen
- From \(1 \text{P}_2\text{O}_5\): \(5\) oxygen
- Total oxygen on the left: \(3 + 5 = 8\)

6. Now consider the right side:
- From \(\text{Ca}_3(\text{PO}_4)_2\): \(8\) oxygen

7. Each side now has:
- Ca: 3
- P: 2
- O: 8

Thus, the balanced equation is:
\[
3 \text{CaO} + 1 \text{P}_2\text{O}_5 \rightarrow 1 \text{Ca}_3(\text{PO}_4)_2
\]

The coefficient in front of \(\text{Ca}_3(\text{PO}_4)_2\) is **1**.