To balance the chemical equation for the reaction of phosphorus (\(P\)) with oxygen (\(O_2\)) to form phosphorus pentoxide (\(P_2O_5\)), we need to determine the correct coefficients.
The unbalanced equation is:
\[ P + O_2 \rightarrow P_2O_5 \]
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Count the atoms of each element:
- On the right side, \(P_2O_5\) has 2 phosphorus (P) atoms and 5 oxygen (O) atoms.
- On the left side, we have \(P\) from the phosphorus and \(O_2\) which contributes 2 oxygen atoms per molecule.
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Balancing phosphorus: To have 2 phosphorus atoms on the left side, we need 2 \(P\):
\[ 2P + O_2 \rightarrow P_2O_5 \]
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Balancing oxygen: We need 5 oxygen atoms on the product side. Since \(O_2\) provides 2 oxygen atoms per molecule, to get 5 oxygen atoms, we can use \(2.5\) molecules of \(O_2\):
\[ 2P + 2.5O_2 \rightarrow P_2O_5 \]
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Eliminating the fractional coefficient: To avoid fractions in the balanced equation, multiply all coefficients by 2:
\[ 4P + 5O_2 \rightarrow 2P_2O_5 \]
Thus, the balanced equation is:
\[ 4P + 5O_2 \rightarrow 2P_2O_5 \]
The coefficients are:
- \(4\) for \(P\)
- \(5\) for \(O_2\)
- \(2\) for \(P_2O_5\)