<span>Day and night are not exactly of equal length at the time of the March and September equinoxes. The dates on which day and night are each 12 hours occur a few days before and after the equinoxes.</span>
Alright, so that means we have 0.68 mol of the compound
For each 1 mol of the compound, we have 4*1 oxygens (because there are four oxygens in the formula)
Therefore for each 0.68 mol of the compound, we have 4*0.68 moles of oxygen!
The mass of the atom would change. With no atoms being there then the mass would possibly change. With no neutrons then the mass of the atom will decrease
the number of moles of oxygen required are 0.08 mol. The volume of oxygen that is required to react can be calculated by the formula shown below. Substitute the values in equation (II). Hence, the volume of oxygen required to react with 3.6 L hydrogen is 1.8L . I hope this helps if not I’m sorry
