Question

What volume of carbon dioxide gas will result from the complete combustion of a `2500*L` volume of propane?

Answer 1

`7500*L` of `CO_2` are evolved.....

Explanation:

You gots your equation:

`C_3H_8(g) + 5O_2(g) rarr 3CO_2(g) + 4H_2O(l)`

And CLEARY this is stoichiometrically balanced. Garbage in equals garbage out.

Now there are 3 moles of product gas per mol of propane reactant. And since `"volume"` of gas is proportional to the number of moles (pressure and temperature constant! which conditions we may reasonably assume), `"THERE MUST BE THREE VOLUMES"` of `CO_2(g)` `"PER VOLUME"` of `C_3H_8(g)`.

SInce we combusted `2500*L` `"propane"` there are thus `3xx2500*L=7500*L` carbon dioxide evolved. That is the stoichiometric coefficients of the balanced chemical equation give you the ratios of the volumes.

You should be able to tell me the volume of dioxygen gas reacted pdq.

Good luck in your final.