Which overall chemical equation is obtained by combining these intermediate equations? Upper C upper H subscript 4 plus 2 upper O subscript 2 (g) right arrow upper C upper O subscript 2 (g) plus 2 upper H subscript 2 upper O (l). Upper C upper H subscript 4 plus 2 upper O subscript 2 (g) right arrow upper C upper O subscript 2 (g) plus 2 upper H subscript 2 upper O (g). Upper C upper H subscript 4 plus 2 upper O subscript 2 (g) right arrow upper C upper O subscript 2 (g) plus 4 upper H subscript 2 upper O (g) plus 2 upper H subscript 2 upper O (l). Upper C upper H subscript 4 plus 2 upper O subscript 2 (g) right arrow upper C upper O subscript 2 (g) plus 6 upper H subscript 2 upper O (g).

The overall chemical equation obtained by combining the intermediate equations is: CH4 + 2O2 → CO2 + 2H2O

According to this question, methane gas reacts with oxygen in a combustion reaction to produce carbon dioxide and water as products.

The chemical equation for the reaction is as follows:

CH4 + O2 → CO2 + H2O

However, the equation is balanced i.e. the number of atoms of each element on both sides of the equation is not the same. We balance the equation using coefficients placed in front of the compound/element as follows:

CH4 + 2O2 → CO2 + 2H2O

Therefore, in words, the correct statement for the balanced equation is: Upper C upper H subscript 4 plus 2 upper O subscript 2 (g) right arrow upper C upper O subscript 2 (g) plus 2 upper H subscript 2 upper O (l).

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it is the most commonly accepted one