Acompound consists of 3.47 grams of oxygen and 1.52 grams of nitrogen. what is the empirical formula of this compound?
a. no
b. n2o2
c. n2o
d. no2

First we need to determine the number of moles of each element.

number of moles O = 3.47/16 = 0.22
number of moles N = 1.52 / 14 = 0.11

Therefore the total number of moles is 0.33

mole percent;

% mol of O = 0.67
% mol of N = 0.33

dividing by the smallest mole percentage, the empirical formula is 

NO2

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