1. The unique property of an element is called:

2. An atom or group of atoms having odd number of electrons is called:

3. Piece of matter in pure form is called:

4. One mole of any material contains chemical units equal to:

5. Which one of the followings is the mixture of oxygen, nitrogen and carbon dioxide?

6. A substance whose atoms have the same atomic number is called:

7. The sum of protons and neutrons in the nucleus of an atom is called:

8. Which one of the followings shows the simplest whole number ratio of atoms in a substance?

9. Which one of the followings has sharp and fixed melting point?

10. Anything that has mass and occupies space is called: