W3 July CS-S3A Chem Mole Concept 2

Sodium azide is an inorganic, ionic compound that has the formula NaN₃ and is used in car airbags. Calculate the number of moles in 130 g of sodium azide.

• 0.5

• 1.0

• 1.5

• 2.0

Calculate the number of molecules present in 10 g of solid calcium carbonate.

• 0.1

• 6 x 10²²

• 1.2 x 10²³

• 3 x 10²⁴

In a blast furnace, carbon in coke is burnt in air to form carbon dioxide. 

C (s) + O₂ (g) → CO₂ (g)

If 25 moles of carbon dioxide are produced daily, what is the volume of carbon dioxide produced?

• 300 dm³

• 400 dm³

• 500 dm³

• 600 dm³

How many atoms are present in 12 dm³ of N₂ gas?

• 1.5 x 10²³

• 3 x 10²³

• 6 x 10²³

• 12 x 10²³

27 g of water was completely boiled. What is the volume of steam that was produced?

• 12 dm³

• 24 dm³

• 36 dm³

• 48 dm³