Answer: NO2
Step-by-step explanation:
Assume 100 grams of a substance so that %=mass in grams
1.) Convert both into moles of each substance
30.45 g N * (1 mol N/ 14.01 g N) = 2.173 mol of N
69.55 g O * (1 mol O/ 16.00 g O) =4.347 mol of O
2.) divide both by the smallest number of moles, in this case 2.173, to find subscripts of each element.
2.173/ 2.173= 1
4.347/ 2.173= 2
Therefore the empirical formula is NO2