Calculations in chemistry - Higher - AQA

1

Which of these is the best definition of a mole?

2

What is the definition of the Avogadro constant?

3

What is the number of molecules in 23 g of NO2? (Mr of NO2 = 46)

4

What is the mass of 0.5 mol of HF gas? (Mr of HF = 20)

5

What is the amount of silver atoms in 216 g of silver, Ag? (Ar of Ag = 108)

6

What amount of O2 reacts with 4 mol of Al?

4Al + 3O2 → 2Al2O3

7

What mass of Al reacts with 96 g of oxygen? Mr of O2 = 32 and Ar of Al = 27.

4Al + 3O2 → 2Al2O3

8

What is a limiting reactant?

9

What is the concentration of a solution formed by dissolving 2 mol of nitric acid in 4 dm3 of solution?

10

What is the volume of 250 cm3 of solution in dm3?