16. Calculate the percentage composition of lithium oxide (Li2O)
(Li=6.94g/mol; O=16.0g/mol
17. What's the percentage composition of dinitrogen tetroxide?
(N=14.0 g/mol; O=16.0 g/mol)
18. What's ther percentage compositoion of a carbon-oxygen compound, given that a 95.2-g sample of the compound contains 40.8 g of carbon and 54.4 g of oxygen?
Please try to give me a great answer, because i need every point i can get in chemistry
2006-11-07 11:17:55 · 2 answers · asked by truckin_90 2 in Science & Mathematics ➔ Chemistry
First of all you need to work out how many grams there are in total, assuming you have 1 mol.
Li2O has 2 Lithium atoms to 1 oxygen, so 6.94x2 = 13.88g of Li and 16g of Oxygen . therefore 13.88+16= 29.88g in total for 1 mol of Li2O.
the rest is a simple percentage calculation.
13.88/29.88x100= your answer for the percentage composition for Lithium
16/29.88x100= your answer for percentage compostion for Oxygen.
same principal for your next two questions. But you have 2 Nitrogen atoms and 4 Oxygen atoms in dinitrogen tetroxide. Just work out the total no of grams and divide the number of grams of each element by the total no of grams in the compound; times by 100 to give you a percentage.
Hope that helps
2006-11-07 11:38:16 · answer #1 · answered by Anonymous · 0⤊ 0⤋
take the mass of each and divided by the total mass
2006-11-07 19:23:45 · answer #2 · answered by 7 · 0⤊ 0⤋