How many moles of hydrogen will react with 40g oxygen

2.5 moles

2H2 + O2 = 2H2O

This implies that 2 moles of oxygen is needed to react with one mole of oxygen to form 2 moles of water

It also implies that

2 moles of hydrogen requires 32 grams of oxygen

? moles of hydrogen would require 40 g of oxygen

2 x 40/32 = 2.5 moles

frequency, z, and the collision density, z, in carbon dioxide (co2), r 180 pm at 30 °c and 120 kpa

c. orbital shape i hope this is correct