Predict the product(s) and write a balanced equation for the following redox reaction:
pentane (C5H12) + oxygen ---->
C5H12 + 8O2 > 5CO2 + 6H2O
hydrocarbons + oxygen=carbon dioxide + water.
Memorize this as the combustion reaction.
To predict the product(s) and write a balanced equation for the redox reaction between pentane (C5H12) and oxygen, we need to consider the combustion of the hydrocarbon.
The combustion of pentane (C5H12) in the presence of oxygen results in the formation of carbon dioxide (CO2) and water (H2O).
The balanced equation for this combustion reaction is:
C5H12 + 8O2 → 5CO2 + 6H2O
To predict the products of a redox reaction, we need to determine the oxidation state of each element involved and balance the equation.
In this case, we have pentane (C5H12) reacting with oxygen (O2). Oxygen is typically in a -2 oxidation state, and since there are two oxygen atoms in O2, the total oxidation state for oxygen is -4. Pentane is a hydrocarbon with only carbon and hydrogen atoms, so each carbon atom has an oxidation state of 0 and each hydrogen atom has an oxidation state of +1.
To balance the equation, we need to determine the ratio between pentane and oxygen. Since oxygen is diatomic (O2), we can balance the carbon atoms first:
C5H12 + O2 ->
There are five carbon atoms on the left side, so we need five carbon atoms on the right side as well. Adding a coefficient of 5 in front of O2 balances the carbon atoms:
C5H12 + 5O2 ->
Next, we balance the hydrogen atoms. There are 12 hydrogen atoms on the left side, so we need 12 hydrogen atoms on the right side. Adding a coefficient of 6 in front of H2O balances the hydrogen atoms:
C5H12 + 5O2 -> 5CO2 + 6H2O
Finally, we balance the oxygen atoms. There are 10 oxygen atoms on the right side from the CO2 molecules, and 12 oxygen atoms on the right side from the H2O molecules. So we have a total of 22 oxygen atoms on the right side. We need to add 22/2 = 11 O2 molecules on the left side to balance the oxygen atoms:
C5H12 + 11O2 -> 5CO2 + 6H2O
Therefore, the balanced equation for the redox reaction is:
C5H12 + 11O2 -> 5CO2 + 6H2O