How many moles of C2H6 are needed to completely react with 4.30 moles of O2 according to the above equation? You must show all your work to receive credit.

Question

The equation is 2C2H6+7O2->4CO2+6H2O

Answer 1

2C₂H₆ + 7O₂ → 4CO₂ + 6H₂O

How many moles ethane are required to react completely with 4.30 moles of oxygen?

Always use the mol/mol ratio between the two molecules given within the equation. Because you want to determine moles of ethane (C₂H₆), moles of oxygen should be placed in the denominator of the fraction (conversion factor) to cancel the unit mol O₂ in your 4.30 mol O₂.

4.30mol O₂ [2mol C₂H₆/7mol O₂] = 1.23 mol C₂H₆

Answer 2

Simple stoichiometry problem: 4.30 mol O₂ /1 x 2 mol C₂H₆ / 7 mol O₂ = 1.23 mol C₂H₆