complete the following table summarizing the amounts of nitrogen and oxygen produced upon the decomposition of the sample of dinitrogen monoxide.

Question

            Mass N2O       Mass N    Mass O
Sample A 2.85 g          1.82 g       1.03 g
Sample B 3.15 g           _____       _____

 

 

Use the Law of Constant Composition

Answer 1

From sample A, you can see that the mass of resulting N is 1.82 / 2.85 = .639 = 63.9% of the mass of the initial N₂O.  And the mass of the resulting O is 36.1%.

 

The same percentages have to hold no matter what the input amount is.

 

So the mass of N in sample B is 63.9% of 3.15 = 2.01 g.

 

And the mass of O in sample B is 36.1% of 3.15 = 1.14 g.