1. 0.4764 g of a sample of oxide of iron was reduced by a stream of CO. 0.3450 g of iron metal remained after reduction. What is the empirical formula of the oxide?
I'm not sure of the approach to this question but I merely subtracted the 2 values and "assumed" oxygen is at 0.1314 g. However after calculations, I got FeO as the answer when the actual answer is Fe3O4. Can someone explain how I can solve this?
2. Complete combustion of a hydrocarbon, Y, yields 2.64 g of CO2 and 2.16g of H2O. What is the empirical formula of the hydrocarbon? (No clue for this question as well)
3. Why is it that in 1 g of H2 gas, there is 1 mole of electrons?
After all,
No, of moles = 1 / (1+1)
=0.5 mol (assuming hydrogen exists as H2 molecules)
Thank you.
1) Your assumption is correct.
No of moles of Fe = 0.3450/55.6 = 6.205X10^-3 mol
No of moles of O = 0.1314/16.0 = 8.213X10^-3 mol
Fe:O = 6.21:8.21 = 3:4
2) Find no of moles of CO2 which is equal to number of moles of carbon in the compund
Then find no of moles of H2O to find no of moles of H atoms
3) 0.5 moles of H2, each molecule has 2 electrons so no of moles of electrons = 1mol