~ Chemistry Crossword ~

7. they react when exposed to air and water but their reactivity is not as strong as that of the alkali metals.
10. Are shiny, malleable, ductile and are good conductors
12. Takes place when 2 or more substances combine to form new substances.
13. Identifies which elements, and how much of each, are in the compound.
14. Chemical reaction that absorbs heat energy
15. found in many different types of animal and plant cells, speeds up the breakdown of hydrogen peroxide into harmless oxygen and water.
16. is the slow chemical change that occurs when oxygen in the air reacts with a metal
17. The new materials produced by the reaction
20. Meaning to go and wonder
21. have both metallic and non-metallic properties.
22. Means below
23. without these, many reactions would require much higher temperatures- a situation that would be deadly to the human body.
24. common example of corrosion- associated with certain metals (;metal gates, car bumpers etc)

1. most reactive metals
2. Most reactive non-metals
3. Are pure substances formed as a result of the attraction between particles of opposite charges
4. sodium bicarbonate
5. Horizontal row
6. meaning 5
7. Is measured by atomic mass unit
8. They can be solids, liquids, or gases at room temperature, insulators and or poor conductors of electricity
9. are substances that help a reaction proceed faster
11. The materials at the start of a reacttion
18. Most stable elements
19. is a chemical reaction that occurs when oxygen reacts with a substance to form a new substance and give off energy.