Nitrogen and oxygen extensive series of oxides with the general formula #N_xO_x#. One of them is a blue solid that comes apart, reversibly, in the gas phase. It contains 36.84% N. What is the empirical formula of this oxide?

1 Answer
Dec 4, 2016

#"N"_2"O"_3#.

Explanation:

Work out the number of moles in #100.00# grams of the oxide.

For nitrogen: The atomic mass of #"N"# is #14.0067#, and we have #36.84" g N"#:

#(36.84" g N")/(14.0067" g N/mol N") = 2.630" mol N"#

For oxygen: The atomic mass of #"O"# is #15.9994#, and we have #100.00-36.84=63.16" g O"#:

#(63.16" g N")/(15.9994" g N/mol N") = 3.948" mol N"#

Now the ratio #3.958/2.630# is very close to #1.5=3/2#. So we conclude that the gas has three moles #"O"# to two moles #"N"# making the empirical formula #color(blue)("N"_2"O"_3)#.