In one on the compounds that contains only oxygen and nitrogen, 3.50 g of nitrogen combines with 2.00 g of oxygen. In another, 0.875 g of nitrogen combines with 1.00 g of oxygen. Show that these compounds obey the law of multiple proportions.
The law of multiple proportions states that if two elements X and Y combine together to form more than one compound, then the several masses of X which chemically combine with a fixed mass of Y is in simple ratio.T
FIRST CASE ;
Molar mass of Nitrogen gas = 28 g/mol
Number of moles of Nitrogen gas = Mass/molar mass = 3.50/28 = 0.125 moles
Number of moles of Oxygen gas = Mass/molar mass = 2.00/32 = 0.0625 moles
Hence the ratio of number of moles of N2 to O2 will be 0.1295 : 0.0625 or 2:1
Similarly for the SECOND CASE ;
Molar mass of Nitrogen gas = 28 g/mol
Number of moles of Nitrogen gas = Mass/molar mass = 0.875/28 = 0.03125 moles
Number of moles of Oxygen gas = Mass/molar mass = 1/32 = 0.03125 moles
Hence the ratio of number of moles of N2 to O2 will be 0.03125 : 0.03125 or 1:1
