The molecular formula of the unknown compound is determined as C₉H₁₁NO₂.
<h3>Molecular formula of the compound</h3>
The molecular formula is calculated as follows;
CHNO + O₂ ------------> CO₂ + H₂O
Mass of carbon, C: = (6.64 x 12)/44 = 1.81 g in 2.77 g sample
Mass of hydrogen, H: = (1.67 x 2)/18 = 0.186 g in 2.77 g sample
Mass of Nitrogen, N: = (2.77 x 0.143)/1.69 = 0.234 g
Mass of oxygen, O: = 2.77 g - 1.81 g - 0.186 g - 0.234 g = 0.54 g
<h3>molar ratio of the elements: </h3>
C = 1.81 g = 0.15 mol
H = 0.186 g = 0.186 mol
N = 0.234 g = 0.017 mol
O = 0.54 g = 0.0337 mol
divide through with the smallest number of moles (0.017 mol);
C = 9
H = 11
N = 1
O = 2
Molecular formula = C₉H₁₁NO₂
Check the molar mass of the compound = (9 x 12) + (11 x 1) + (14) + (2 x 16) = 165 g/mol
Thus, the molecular formula of the unknown compound is determined as C₉H₁₁NO₂.
Learn more about molecular mass here: brainly.com/question/21334167
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