1. Unit 1 cda review 2017

2. 1. Each substance in the mixture keeps its own set of properties and can be separated.
2. A single kind of matter that is pure( it always has a specific make up or composition) and has a specific set of properties.

3. 3. True: They are made up of atoms with specific properties.
4. When the mixture is separated into the 3 original substances, each substance retains its own properties.
5. a mixture (heterogeneous)
6. They all have a definite chemical composition.

4. 7. By the number of protons the element has in the nucleus (the atomic number)
8. Metalloids are elements that have the both metal and non metal properties or characteristics.
9. The atomic number tells you the number of protons in the nucleus of the atom and the number of electrons in the electron cloud.

5. 1o. They are shown on the periodic table in the same column (group/family).
11. The elements share common characteristics or properties.
12. metal – metalloid- non metals-gases
Most reactive to least reactive
13. It tells you how many of that particular atom you have in the compound. 2 Hydrogen, 1 Sulfur, and 4 Oxygen

6. 14.
15. Rusting
16. Volume and mass
17. decomposes and reacts with water
18. True
19. The substance changes form but does not lose its identity.

7. 20. Indefinite shape
21. The molecules move farther apart because the substance absorbs heat (endothermic) energy.
22. The molecules slow down and will eventually form a solid because more heat is taken away(exothermic).

8. 23. The molecules move farther apart because the substance absorbs heat (endothermic) energy.
24.

9. 25. The mass of the wick, the candle wax, and oxygen before the reaction is the same or is equal to the mass of the smoke, ash, and gas after the reaction.
26. It is equal to the mass of the Carbon plus the mass of the Oxygen.