1. Matter and its Changes

2. Atoms Matter is made up of atoms Matter is anything that takes up space and has mass Atoms are the “building blocks” of life

3. Forms of matter that contain only one type of atom are called elements Atoms combine to form many different types of matter

4. Structure of an Atom Proton Electron (electron cloud) Neutron Mass Number = Protons + Neutrons Atomic Number = Number of protons

6. Isotopes When the number of protons in an atom changes it becomes a different element Atom is electrically neutral when there are more neutrons than protons Atoms of the same element that have a different number of neutrons are called isotopes Ex. C 12 = 6p +6n C 14 = 6p + 8n

8. Ions Electrically charged atoms are called Ions The number of protons is not equal to the number of electrons Ions are attracted to each other when they have opposite charges Ex. Na + + Cl - = NaCl = salt Ex. Na + + F - = Sodium Fluoride for toothpaste

9. Combinations of Atoms

10. Atoms combine by sharing their outermost electrons in their electron clouds When two atoms are combined a molecule is formed

11. Bonds Ionic Bond – Positive and Negative ions combine and electrons are transferred –Ex. NaCl Covalent Bond – Electrons are shared –Ex. H 2 O

13. Combinations of Atoms

14. How Atoms Combine When at least two atoms are combined a molecule is formed There are two ways in which atoms combine to form molecules and compounds

15. Ionic Bonding Positive and Negative ions combine and electrons are transferred Example: Na + and Cl - = NaCl

16. Covalent Bonding In covalent bonding electrons are shared Example: 2H + O = H 2 O

17. Compound A type of matter that has properties different from the properties of each of the elements in it Example: Na (metal) + Cl (gas) = NaCl (solid salt) Example: 2H (gas) + O (gas) = H 2 O (liquid water)

18. Mixture Many different substances that when mixed together, each substance retains its own properties Examples: sand, air and salad

19. Solution When one substance of a mixture is dissolved in another substance it is a solution Examples: tea w/ sugar, salt water

20. Chemical properties describe how one substance changes when it reacts with another Examples: iron and oxygen = rust Physical Properties can be observed or measured without changing the substance Examples: color, shape, size, density and texture

21. Density

22. What is density? The measure of the mass of an object divided by its volume.

23. 4. Liquid to a solid: freezing point 5. Solid to a liquid: boiling point 6. Only substance that occurs naturally as a solid, liquid, and gas: Water

24. Matter can change by: 1.Increasing or decreasing the temperature Ex: freezing water turns it to a solid (ice) 2. Increasing or decreasing pressure Ex: Pressure to ice cube changes it to liquid

25. Energy from Atoms 1.What is nuclear energy? -Alternate energy source produced from atomic reactions 2. How fission produces nuclear energy: - Splitting the nucleus of atoms in heavy elements

26. 3. Most commonly used fuel in nuclear power plants: - Uranium 235 Where is it found? - Sandstones in the Rocky Mountains

27. 4. Major source of nuclear waste: - Radioactive material Most common method of storing nuclear waste: -Power plants Can remain active for 10,000 years

28. Two advantages to storing nuclear waste at Yucca Mountain: 1.Remote area (deserted) 1.Water table is far below storage facility

29. Two disadvantages to storing nuclear waste at Yucca Mountain: 1.Earthquakes could destroy storage facility 2.Large amount of nuclear waste in one area