Atoms and Molecules-Important Questions

1.  Define polyatomic ion. Give one example.

2.  What is formula unit of mass? How is it different from molecular mass?

3.  What is Law of conservation of mass and Law of constant proportions?

4.  What is an ion? Explain the types of ion with examples.

5.  Find the molecular mass of H₂O.

6.  Define the term valency. What is the valency for magnesium and copper?

7.  What is the difference between cation and anion?

8.  What is atomicity? What is the atomicity of phosphorus and nitrogen?

9.  Find the number of atoms in 0.5 mole of C atom.

10.  Find the mass of 1.5 mole of CO₂ molecule.

11.  Calculate the formula unit mass of NaCl and CaCl₂.

12.  What is the difference between molecules 2O and O₂?