1. What are the signs that a chemical reaction has taken place?

2. Atomic Structure

3. U-236 Number of protons Number of electrons Number of neutrons Ion, element or isotope?

4. Define the following and give an example

5. Substance

6. Heterogenous

7. Compound

8. Homogeneous

9. Mixture

10. Differentiate between independent and dependent variables

11. Percent Composition C 6 H 12 O 6

12. Empirical and molecular formulas 38.67% C 16.22% H 45.11% N Molar mass = 124 g/mol

13. Calculate the quantity of energy needed to heat 8.0 g of water from 42.0 degrees Celsius to 45.0 degrees Celsius.

14. Chemical formulas

15. Calcium chloride

16. Sodium acetate

17. Copper (II) sulfate

18. Magnesium phosphate

19. Balance the following and tell me what type of reaction it is

20. Copper + sulfur produces copper (I) sulfide

21. Silver nitrate + aluminum chloride produces silver chloride + aluminum nitrate

22. Chromium (III) carbonate breaks down into chromium (III) oxide + carbon dioxide