I need help!!!!! the chemical equation for quartz is SiO2 How many Oxygen atoms are in 1.20g of quartz Please help me with this equation... there is something that Iam missing and I don't know what. I need help!!!!! the chemical equation for quartz is SiO2 How many Oxygen atoms are in 1.20g of quartz Please help me with this equation... there is something that Iam missing and I don't know what. How many Oxygen atoms are in 1.20g of quartz Please help me with this equation... there is something that Iam missing and I don't know what.
Explanation / Answer
For this problem you need two things. Avagadros numberof 6.022*10^23, and a periodic table. Fromt he periodic tableyou can find the atomic weight per mol for each element. Foroxygen it is 16 g/ mol (Some say 15.999) and for Si it is 28.088g/mol. You can add these together to find the molar mass ofthe molecule. 28.088 + 2*16 = 60.088 g/mol. Now you can find howmany mole of quartz molecules are in the 1.20 g sample by dividingthe weight by the molar mass 1.2/60.088=.02 mol SiO2 NOw for every mol of molecule there are two moles of oxygenatoms. .02 * 2 = .04 mol O. Now use avagadro number to find the number of oxygenatoms. .04*6.022*10^23= 2.4 * 10^22 atoms of oxygen. You can also convert the mol of the molecule to number ofmolecules and then times that by two for atoms of oxygen you stillget the same number.