I'm not suree.. is his science?
M Fe = 55,85g ≈ 56g
m O = 16g
m N = 14g
m Fe(NO3)3 = 56g + 3*14g + 3*3*16g = 242g/mol
answer: (4)
Sugar, on the other hand, is composed of carbon, oxygen, and hydrogen and has covalent bonds. A salt molecule is made up of one sodium atom and one chlorine atom.
The equation is: C+O2=>CO2
Since we got 10 molecules of CO2 new balanced equation would be 10C+10O2=>10CO2
from this equation we can see that we have 10 molecules of oxygen, however ,we need to find atoms. There are 2 atoms in the oxygen molecule so we need to multiply 10 by 2 which gives us 20 atoms.
The answer: there are 20 atoms of oxygen