Atoms and Molecules

Atoms and Molecules Worksheet-7

11. Calculate the number of Mg atoms in 0.024 g of Mg.

12. Write the names of the compounds represented by the following formulae :

(i) Al₂(SO₄)₃               (ii) CaCl₂            (iii) K₂SO₄

(iv) KNO₃                    (v) CaCO₃.

13. Calculate the number of moles of 52 g of He.

14. Calculate the number of particles in 0.1 mole of carbon atoms.

Atoms and Molecules Worksheet-8

21. What is the mass of 0.2 mole of oxygen atoms?

22. Calculate the number of molecules of sulphur (S₈) present in 16 g of solid sulphur.

23. Calculate the number of aluminium ions in 0.051 g of aluminium oxide (Al₂O₃).

24. The mass of an atom of element (X) is 2.0 × 10^–23 g. Calculate its atomic mass.

25. Calculate the molar mass of Nitric acid.

26. What is number of molecules present 1.5 mole of ammonia (NH₃) ?