What is the chemical equation to show the combustion reaction of ethanol?

1 Answer
Nov 2, 2015

Answer:

#"C"_2"H"_6"O(l)" + color(orange)3"O"_2"(g)"##rarr##color(red)2"CO"_2("g") + color(purple)3"H"_2"O(l")#

Explanation:

#"C"_2"H"_6"O(l)" + "O"_2"(g)"##rarr##"CO"_2("g") + "H"_2"O(l")#

Balance the Equation:

Balance the #"C"# and #"H"# first. There are #2# carbon atoms on the left side, and #1# carbon atom on the right side. There are #6# hydrogen atoms on the left side and #2# hydrogen atoms on the right side.

Add a coefficient of #color(red)2# in front of the carbon dioxide, and a coefficient of #color(purple)3# in front of the water.

#"C"_2"H"_6"O(l)" + "O"_2"(g)"##rarr##color(red)2"CO"_2("g") + color(purple)3"H"_2"O(l")"#

We now have equal numbers of #"C"# and #"H"# atoms on both sides. However, the #"O"# is not balanced.

We have #7# #"O"# atoms on the right side, and #3# on the left side. Place a coefficient of #color(orange)3# in front of the #"O"_2# on the left side.

#"C"_2"H"_6"O(l)" + color(orange)3"O"_2"(g)"##rarr##color(red)2"CO"_2("g") + color(purple)3"H"_2"O(l")#

We now have a balanced equation, with #2# carbon atoms on both sides, #6# hydrogen atoms on both sides, and #7# oxygen atoms on both sides.