I don't understand why the molar mass is given. Couldn't I work with the first part of the question? Thanks.
2006-12-11 19:53:07 · 4 answers · asked by nandemonai 2 in Science & Mathematics ➔ Chemistry
1) convert the masses to moles
Nitrogen: 6.44 g / 14.01 g/mol = 0.460 mol
Oxygen: 14.72 g / 16.00 g/mol = 0.920 mol
2) divide each molar amount by the lowest value to obtain small integers
Nitrogen: 0.460 / 0.460 = 1
Oxygen: 0.920 / 0.460 = 2
The empirical formula of the substance is (NO2)k.
To find k we use the molar mass of the compound. NO2 has molar mass 46, therefore k must be 2.
The molecular formula is N2O4.
2006-12-11 19:59:35 · answer #1 · answered by cordefr 7 · 0⤊ 0⤋
Theoretically NO2 has a molecular weight of: N = 14 O = 2 x 16 = 32 NO2 = 46g/mole From the given data, using the ideal gas law which is: PV = nRT or PV = mRT/M where; m = mass of the substance M = Molecular weight of the substance then; M = mRT/PV = 46.485 gram/mole (molar mass) hence; Molecular formula = molar mass / mass of emperical formula = 1 Molecular formula is the same as the emperical formula
2016-05-23 08:08:02 · answer #2 · answered by Anonymous · 0⤊ 0⤋
the rate of weight of oxygen to nitrogen is 2.286
The proportion of oxygen in the compound is 2.286/(2.286-1)
on 92 g the mass oxygen would be 2.286 *92/(2.286+1)= 64
So, there are 4 atoms of oxygen in the compound since the mass of oxygen is 16
the mass of Nitrogen is 92-64 =28 corresponding to 2 atoms nitrogen
The formula of the compound is N2O4
The molecular mass is given to avoid you write only NO2
2006-12-11 21:11:54 · answer #3 · answered by maussy 7 · 0⤊ 0⤋
easy, N2O4
2006-12-11 21:25:45 · answer #4 · answered by Cyrill sneer 2 · 0⤊ 1⤋