If given 0.811 mol of oxygen in CO2, how many mol of C will there be?

Answer 1

It is important to understand if the oxygen is referring to diatomic oxygen or just oxygen.

If we are to assume that it is just asking about oxygen, then we next look at the subscripts of CO₂.In CO₂, there is an unwritten 1 following the carbon and a 2 following the oxygen. This means that there will be 2 moles of oxygen for every 1 mole of carbon. In other words, there will be twice as many moles of oxygen as there are carbon.

All we need to do is divide the moles of oxygen by 2 and we will have the moles of carbon. 0.811 / 2 = 0.4055.

This means that there are 0.4055 mol of carbon in 0.811 moles of oxygen.