The following equation represents the combustion of propane gas. C3H2(g) + 5O2(g) --> 3CO2(g) + 4H2O(1) + heat
How many grams of H20 are produced by the combustion of 687 grams of
propane gas (assuming unlimited oxygen)?

it should be all of them because it asks if you included all of those in your answer

explanation:

when [oh-] is 10-5  m, and [h3o+] is 10-9  m, the poh is 5 and ph is 9. again in both cases the sum of ph and poh is 14. however, the hydrogen ion concentration is not always going to be equal to exactly 1 x 10 raised to a negative number. for example, we skipped over the value of 2.0 x 10-7.

is it d? cause im still confusion