A compound is 25.9% nitrogen and 74.1% oxygen find the empirical formula

Let suppose the compound weights 100 g,

Nitrogen = 25.9 % = 25.9 g

Oxygen = 74.1 % = 74.1 g

Compound = Nitrogen + Oxygen

Compound = 25.9 g + 74.1 g = 100g

Calculate moles of Nitrogen and Oxygen,

As,

Mole = mass / M. mass

For Nitrogen,

Mole = 25.9 g / 14.0 g/mol

Mole = 1.85 moles of Nitrogen

For Oxygen,

Mole = 74.1 g / 15.999 g/mol

Mole = 4.631 moles of Oxygen

Now finding Ratio of Nitrogen to Oxygen,

Nitrogen : Oxygen

1.85 : 4.631

Now,

Dividing this ratio with 1.85 as it is the lowest number,

So,

(1.85 : 1.85) : (4.631 : 1.85)

1 : 2.50

Multiply this ratio with 2 so that a whole numbers are obtained

(1 : 2.50) * 2

Result:

2 : 5

There are 2 Nitrogen atoms and 5 Oxygen atoms in this compound.

N₂O₅ (Empirical Formula)