Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
Assign oxidation numbers to each atom in the following combustion reactions and then tell which combustion reaction is?
least efficient:
C8 H18 + 17/2 O2 ⇨ 8 CO + 9 H2O
C8 H18 + 9/2 O2 ⇨ 8 C + 9 H2O
C8 H18 + 25/2 O2 ⇨ 8 CO2 + 9 H2O
1 Answer
- electron1Lv 72 years ago
The electronegativity of carbon is 2.5. For hydrogen, it is 2.1. This means carbon has a negative charge, and hydrogen has a positive charge. 8 C’s is +8. 18 H’s is -8. The oxidation number of each hydrogen atom is -4/9. In carbon dioxide, the oxidation number of oxygen is -2.
C + 2 * -2 = 0
C = +4
The same thing is true for water. Oxygen is -2. So hydrogen is +1. C8 H18 has 8 carbon atoms and 18 hydrogen atom. This will produce 8 molecules of CO2, and produce 9 molecules of H2O. This will produce 8 molecules and 4.5 molecules of O2. This is 12.5 molecules of oxygen. The last equation is the only correct equation. I hope this is helpful for you.
