Question

What is the coefficient in front of the O₂ when the equation below is balanced C₂H₆O₂(g) + O₂ (g) → CO₂(g) + H₂O (g)

Answer 1

The balanced equation is:

2C₂H₆O₂ (g) + 5O₂ (g) → 4CO₂ (g) + 6H₂O (g)

Therefore, the coefficient in front of O₂ when the given equation is balanced is 5.

Step-by-step explanation:

In order to balance a chemical equation, it is necessary to ensure that there is an equal number of atoms for each element on both sides of the equation. This can be achieved by adding coefficients to chemical symbols or formulas as required.

Given equation:

C₂H₆O₂ (g) + O₂ (g) → CO₂ (g) + H₂O (g)

This equation is not balanced, because there are:

• 2 carbon atoms on the left side of the equation and only one on the right side.
• 6 hydrogen atoms on the left side of the equation and only 2 on the right side.
• 4 oxygen atoms on the left side of the equation and only 3 on the right side.

Add the coefficient 2 in front of CO₂ and the coefficient 3 in front of H₂O on the right side of the equation:

C₂H₆O₂ (g) + O₂ (g) → 2CO₂ (g) + 3H₂O (g)

The carbon and hydrogen atoms are now balanced, but there are 4 oxygen atoms on the left side and 7 oxygen atoms on the right side. To balance the equation, double the coefficients on the right side and add the coefficient 2 in front of C₂H₆O₂ on the left side of the equation:

2C₂H₆O₂ (g) + O₂ (g) → 4CO₂ (g) + 6H₂O (g)

Now we have 6 oxygen atoms on the left side and 14 oxygen atoms on the right side. So if we add the coefficient 5 in front of O₂, there are14 oxygen atoms on the left side, and thus the equation is balanced.:

2C₂H₆O₂ (g) + 5O₂ (g) → 4CO₂ (g) + 6H₂O (g)

`\begin{array}c\cline{1-3}\vphantom{\frac12}&\sf Left\;side&\sf Right\;side\\\cline{1-3}\vphantom{\frac12}\sf Carbon&2 * 2=4&4\\\cline{1-3}\vphantom{\frac12}\sf Hydrogen&2 * 6=12&6 * 2=12\\\cline{1-3}\vphantom{\frac12}\sf Oxygen& 2* 2+5 * 2=14&4 * 2+6 =14\\\cline{1-3}\end{array}`

Therefore, the coefficient in front of O₂ when the given equation is balanced is 5.