Question

A molecular compound is found to consist of30.4% nitrogen and 69.6% oxygen. Ifthe molecule contains 2 atoms of nitrogen, what is the molar mass of the molecule

Answer 1

To calculate the molar mass of the molecule, the mass of nitrogen and oxygen needs to be calculated separately. Based on the given information, the molar mass of the molecule is 99.2 g/mol.

Step-by-step explanation:

To find the molar mass of the molecule, we need to calculate the mass of nitrogen and oxygen separately. Since the compound consists of 30.4% nitrogen and 69.6% oxygen, we can assume that the total mass of the molecule is 100 grams. From the given information, we know that there are 2 atoms of nitrogen in the molecule.

We can calculate the mass of nitrogen by multiplying the percentage by the total mass:

Mass of Nitrogen = (30.4/100) x 100 g = 30.4 g

Since there are two atoms of nitrogen, the mass of one nitrogen atom would be half of the total mass of nitrogen:

Mass of one Nitrogen atom = 30.4 g / 2 = 15.2 g

The molar mass of the molecule would be the sum of the mass of two nitrogen atoms and the mass of oxygen:

Molar Mass = (2 x 15.2 g) + (69.6 g) = 99.2 g/mol

Answer 2

92.01 g/mol

Step-by-step explanation:

So first you need to find the empirical formula by the percents. That would be, assuming that you have 100 grams of the the sample, divide each quantity of each element found by its respective molar mass.

30.4 g of N ÷ 14 g/mol N= 2.17 mol of N

69.6 g of O ÷ 16g/mol= 4.35 mol of O

You can establish now the empirical formula.

N2.17O4.35,

but since you can't have a decimal subscript, you divide each subscript by the minimum subscript

NO2

So then you're said that the molecular formula derived from that empirical formula has 2 nitrogen, so you multiply all the subscripts, by 2:

N2O4

-Dinitrogen Tetraoxide

-Nitrogen oxide (IV)

Then all you have to do is find the molecular mass of the compound using the periodic table and what you obtain is the molar mass.

remember: molecular mass is correspondent to molar mass.