How many moles of o2 are needed to react completely with 35.0 mol c2h2

Hey There!:

2 C2H2 + 5 O2 = 4 CO2 + 2 H2O

2 moles C2H2 5 moles O2

35.0 moles C2H2 moles O2

moles O2 = 35.0 * 5 / 2

moles O2 = 87.5 moles

hope this helps!

atomic number of carbon is 6

electronic configuration of carbon is 1s²2s²2p²

orbital diagram of carbon is as shown here in the image.