Oxygen is a diatomic gas. How many oxygen molecules are in 16 grams of oxygen?

A) 0.5 molecules

B) 1.20 x 1024 molecules

C) 3.01 x 1023 molecules

D) 6.02 x 1023 molecules

3.011 * 10²³ O₂ Molecules

Explanation:

Data Given:

Mass of O₂ = 16.0 g

M. Mass of O₂ = 32.0 g. mol⁻¹

Step 1: Calculate Moles of O₂ as,

Moles = Mass : M. Mass

Putting values,

Moles = 16.0g : 32.0 g. mol⁻¹

Moles = 0.50 mol of O₂

Step 2: Calculate number of Carbon atoms,

As 1 mole of any substance contains 6.022 * 10²³ particles (Avogadro's Number) then the relation for Moles and Number of Oxygen Molecules can be written as,

Moles = Number of O₂ Molecules : 6.022 * 10²³ Molecules. mol⁻¹

Solving for Number of C atoms,

Number of O₂ Molecules = Moles * 6.022 * 10²³ Molecules. mol⁻¹

Putting value of moles,

Number of O₂ Molecules = 0.50 mol * 6.022 * 10²³ Molecules. mol⁻¹

Number of O₂ Molecules = 3.011 * 10²³ O₂ Molecules