Answer:
20 moles
Step-by-step explanation:
we are given the equation, propane is C3H8. I'll put 1 in front of C3H8 to show you the ratios. The right side of the equation is not needed.
1C3H8+ 5O2
1 : 5
4 moles : x moles
working out x:
to get from 1 to 4 in C3H8 multiply by 4, so do the same to the other side for O2
5 × 4 = 20, so 20 moles are necessary to react completely with four moles of propane