Given the incomplete equation for the combustion of ethane, #2C_2H_6 + 7O_2 -> 4CO_2 + 6__#, what is the formula of the missing product?

1 Answer
Jan 6, 2016

Answer:

#H_2O#, aka water.

Explanation:

In general any organic compound, when burned will generate an "oxide" of its atoms.

Carbon goes to #CO# or #CO_2# (the latter, if complete)
Hydrogen goes to #H_2O#
Nitrogen and Sulfur depend on the amount of #O_2# available. If the amount is big enough they'll go for higher oxidation states such as #NO_2#, #SO_3# but with less oxygen they'll settle for lower states like #NO# and #SO_2#

Another way to solve this is to count the atoms that aren't in the right side. If you do the math you'll see we're missing 12 Hydrogen atoms and 6 Oxygen atoms, dividing by the stoichiometric coefficient that was given, we have 2 Hydrogen atoms and 1 Oxygen atom together to make a compound, which is obviously water.