CROSSWORD 1

6. An atom may be regarded as the _______ particle of an element that can exist.
8. Lithium, Sodium, Potassium etc. have ____ valency.
9. Boron, Aluminum, Galium etc. are ____ conductors.
10. Name of material whose atomic number is 6.
12. Materials which have 7 electrons in their outer shell are Good __________.
13. Central part of an atom is called as _______.
14. Classification of materials used in engineering can be done on the basis of their __structure.

1. Molecules can be subdivided chemically into minute particles known as ______.
2. _______ has a positive electrical charge.
3. An example of semiconductor material.
4. This type of energy is most convenient form of energy and has many applications.
5. Matter is made up of extremely small particles known as _______.
7. ________ has no charge at all.
11. ____ has the main role to classify any material on the basis of its atomic structure.
15. The materials which have three electrons in their outer shell are called ___ Valent materials.