Question

4. How many moles of oxygen gas are needed to react completely with
3.0 moles of C2,H6.?

Answer 1

Hey there!:

Mole ratio :

2 C₂H₆ + 7 O₂ → 4 CO₂ + 6 H₂O

2 moles C₂H₆ -------------------- 7 moles O₂

3.0 moles C₂H₆ ------------------ moles O₂ ??

moles O₂ = 3.0 x 7 / 2

moles O₂ = 21 / 2

moles O₂ = 10.5 moles of O₂

Hope this helps!