How to Convert Molecules of Oxygen to Moles of O₂

Which Equivalence Factor should you use to convert from 4.28 x 10¹⁹ molecules of oxygen (O₂) to moles of O₂?

A. 1 mol O₂ / 4.28 x 10¹⁹ molecules O₂

B. 4.28 x 10¹⁹ molecules O₂ / 1 mol O₂

C. 1 mol O₂ / 6.02 x 10²³ molecules O₂

D. 6.02 x 10²³ molecules O₂ / 1 mol O₂

The answer is: C. (1 mol O₂ / 6.02 x 10²³ molecules O₂)

Answer:

The equivalence factor is 1 mole / 6.023 x 10²³ molecules.

Explanation:

Avogadro's Number or Avogadro's Constant is called the number of particles that make up a substance (usually atoms or molecules) and that can be found in the amount of one mole of said substance. Its value is 6.023 x 10²³ particles per mole. The Avogadro number applies to any substance.

A rule of three can be applied as follows: if 6.023 x 10²³ molecules are contained in 1 mole, how many moles will be contained in 4.28 x 10¹⁹ molecules?

moles = 4.28 x 10¹⁹ molecules * (1 mole / 6.023 x 10²³ molecules)

moles ≈ 7.106 x 10⁻⁵

So, the equivalence factor is 1 mole / 6.023 x 10²³ molecules.