Across
- 2. A system of easy-to-use warning symbols on hazardous materials
- 4. Vertical column of elements in the periodic table
- 5. They are used to describe matter, like colour or conductivity
- 9. States that mass cannot be created or destroyed
- 10. Occurs when two or more materials react and create new materials
- 12. Chemical reaction that absorbs energy
- 13. Slow chemical change that occurs when oxygen in the air reacts with a metal
- 15. Number of protons in the nucleus of one atom of an element
- 19. Chemical reaction that releases energy
- 20. A table in which elements are organized by their physical and chemical properties
- 21. Pure substance formed when at least one metal and one non-metal combine
- 22. A positively charged particle
- 23. Chemical reaction that occurs when oxygen reacts with a substance to form a new energy and give off energy
- 24. Matter which has a specific composition and specific properties / every pure element
Down
- 1. an atom with a neutral charge is one where the number of electrons is equal to the atomic number
- 3. The most reactive non-metals
- 5. Occurs when a material changes from one state o another
- 6. New substance produced in a chemical reaction between reactants
- 7. Elements that have both metallic and non-metallic properties
- 8. Pure substance formed when non-metals combine
- 11. Anything that has mass and takes up space
- 14. Horizontal row of elements in the periodic table
- 16. Pure substance that cannot be broken down into other substances
- 17. Mass of one atom of an element
- 18. Substance that reacts with another substance in a chemical reaction to create new substances with different propeties