A compound that only contains the elemens nitrogen and hydrogen can be catalytically oxidised to form nitrogen gas and water. When a sample of this compound is completely oxidised by this process the mass of water formed was found to be 3.07g and the volume of dry nitrogen gas collected at SLC was 2.69L.
a) calculate the mass of nitrogen atoms present in this sample of the compound.
b) calculate the mass of hydrogen atoms present in this sample of the compund
c) determine the empirical formula for this compund.
2007-03-11 14:24:01 · 2 answers · asked by mayeham7 1 in Science & Mathematics ➔ Chemistry
Start with water which is H2O
H2= (2/18) 3.07 mol wt of water =18
H2= 0.341 moles
Since we want atoms, we multily this by 2, and then by 6.02x10^23.
For nitrogen, if we had one mole, it would occupy 22.4 liters, so we have 2.69/22.4 moles or 0.12 moles. Since we want atoms and nitrogen gas is N2, we again multiply by 2 and then by 6.02x10^23.
The empirical formula is the mole ratio of N to H or NH3
2007-03-11 14:35:27 · answer #1 · answered by cattbarf 7 · 0⤊ 0⤋
For a) use the ideal gas law PV=znRT to calculate n the number of moles of nitorgen from the 2.69 L of nitrogen at standard conditions from which you can calculate the mass of nitorgen..
b) calculate the number of moles of water which would be equal to the number of moles of H2 from which you cal calculate the mass of hydrogen
c)then calculate the empirical formula for the compound.
2007-03-11 14:55:58 · answer #2 · answered by Scooter 1 · 0⤊ 0⤋