Across
- 2. Positive ions are called
- 4. The layer of earth that protects the surface from harmful solar radiation
- 5. Small pieces of frozen rain
- 8. NH3
- 10. It is defined as mass divided by volume
- 12. Anything that has mass & volume
- 13. Unit of measurement of time
- 14. Blue litmus paper turns _______ under acidic conditions
- 15. Centre of atom is called ________
- 17. A process through which solid is separated from liquids
- 18. A process through which liquid changes to solid
- 19. Indivisible and single unit of matter
Down
- 1. Natural magnets are also called
- 3. Study of matter and the changes it undergoes
- 6. Strong base that dissolves in water
- 7. 70% of earth is made up of
- 9. First element in the periodic table
- 11. Earth is the 3rd planet from the ______
- 12. The only metal that is liquid in room temperature
- 16. Snow mixed with rain