1. Composition of Matter Atom= building block of an element Smallest part of matter Protons= + charge Neutrons= 0 charge Electrons= -1 charge

2. Protons & neutrons= IN NUCLEUS Electrons= Orbit OUTSIDE nucleus

3. Subatomic Particles Proton: positive charge, +1 mass, in nucleus Neutron: no charge, +1 mass, in nucleus Electron: negative charge, 0 mass, outside nucleus ***# of protons ALWAYS = # Electrons

5. Identifying Elements: Atomic Number: number of protons in an element Zr=40 protons…and _______electrons Mass Number: Protons + neutrons H= 1 mass # He=4 mass #

6. 11 12 Sodium Atomic number = Mass Number = 2 - 8 - 1 p+p+ n 23 11 23 protons & neutrons 12 neutrons In a neutral sodium atom the number of protons (11) = the number of electrons (11) - 11 protons __________________ __

7. 4 5 Beryllium Atomic number = Mass Number = 2 - 2 p+p+ n 9 4 9 protons & neutrons 5 neutrons In a neutral beryllium atom the number of protons (4) = the number of electrons (4) - 4 protons __________________ __

8. 7 7 Nitrogen Atomic number = Mass Number = 2 - 5 p+p+ n 14 7 14 protons & neutrons 7 neutrons In a neutral nitrogen atom the number of protons (7) = the number of electrons (7) - 7 protons __________________ __

9. 16 Sulfur Atomic number = Mass Number = 2 - 8 - 6 p+p+ n 32 16 32 protons & neutrons 16 neutrons In a neutral sulfur atom the number of protons (16) = the number of electrons (16) - 16 protons __________________ __

10. 14 Silicon Atomic number = Mass Number = 2 - 8 - 4 p+p+ n 28 14 28 protons & neutrons 14 neutrons In a neutral silicon atom the number of protons (14)= the number of electrons (14) - 14 protons __________________ __

11. 19 20 Potassium Atomic number = Mass Number = 2 - 8 - 8- 1 p+p+ n 39 19 39 protons & neutrons 20 neutrons In a neutral potassium atom the number of protons (19) = the number of electrons (19) - 19 protons __________________ __

12. Periodic Table Columns on the table are called Groups Group # is # of valence electrons Rows are called Periods Period # tells how many shells you have

13. Atomic Weight & Isotopes Isotopes= same # of protons & electrons, but DIFFER in neutrons Ex) Hydrogen, H2, H3 They still have same chemical properties Radioisotopes= heavier isotopes that are unstable and decay Can be harmful to cells Can be used to tag biological molecules

14. Chemical Compounds Chemical combination of 2 or more elements Water = H 2 O A compound can behave differently than the elements that make it up Ex) Water. Hydrogen is gas, Oxygen is gas. Together they form a liquid.

15. Types of Chemical Bonds: Ionic Bond: when electrons are transferred from one element to another When an atom gains electrons, it becomes negatively charged and is called Anion. Cation = positive charge, when element gave up electron

16. Covalent Bonds: When atoms share electrons The valence shell is satisfied by both molecules

17. Van der Waals Forces When atoms share electrons, sharing is not always equal. + and – charges attract to each other

18. Water Polarity Because of unequal distribution of electrons, water is polar. Negative pole of oxygen is attracted to the positive pole of hydrogen

19. Solutions & Suspensions Solutions=all components in a mixture are equally distributed Suspensions= mixture of water and undissolved solutes Solute=substance dissolved Solvent=dissolves solute

20. Acids and Bases Acids=produces H ions Value below 7 Bases=produce OH ions Value above 7 Look on pg. 43

21. pH Scale Created to indicate the concentration of H ions. Low # = acid High #= base

22. Carbon Compounds Organic Chemistry is the study of all compounds containing carbon Carbon can form millions of different bonds 4 types of compounds: CarbsNucleic acids LipidsProteins

23. Carbs= main source of energy Proteins= form bones, muscles, made of amino acids Nucleic Acids= store/transmit genetic information Lipids= store energy, make up membranes