1. Basic Chemistry This is building upon the info on the website. Make sure you review and ask questions.

2. Chemical Bonds, Molecules, & Compounds Bond is union between electron structures of atoms Atoms bond to form molecules Molecules may contain atoms of only one element - O 2 Molecules of compounds contain more than one element - H 2 O

3. 2 Important types of Bonds found in Biological Molecules Ionic Bonds Covalent Bonds

4. Ionic Bonding This bond is the transfer of electrons from one atom to another One atom loses electrons, becomes positively charged ion o Another atom gains these electrons, becomes negatively charged ion o Charge difference attracts the two ions to each other

5. Formation of NaCl electron transfer sodium atom 11 p + chlorine atom 17 p + 17 e - chlorine ion 17 p + 18 e - sodium ion 11 p + 10 e -

7. Think Pair Share Think of a mneumonic device that will help you to remember the names and charges of ions.

8. Covalent Bonding Atoms share a pair or pairs of electrons to fill outermost shell (valence)no giving or taking of electrons

9. molecular oxygen (O 2 ) O=O Two oxygen atoms, each with six electrons, would like to fill their valence (need 2 more electrons each). So the 2 atoms share four electrons in a covalent bond. Fig. 2-8b(2), p.25 Covalent Bonding

10. water (H 2 O) H—O—H Oxygen has vacancies for two electrons in its outer orbital. Two hydrogen atoms can each share an electron with an oxygen. The result is a covalent bond forming a water molecule. Fig. 2-8b(3), p.25 Covalent Bonding Bonding Video

11. How to tell Ionic or Covalent?? Typically covalent bonds are formed between atoms of the same element and when more than 2 atoms are involved in the bond.

12. Think Pair Share

13. Hydrogen's bonding to carbon, nitrogen, other hydrogen's These are special bonds important to bio.

14. So now that you have the basics of chem, what’s your body doing with all these chemicals and bonded atoms? Before we can answer that, you need to know that all living creatures MUST follow the Physical Laws of our planet. 1 st Law of Thermodynamics: energy/mass can not be created or destroyed, only converted. 2 nd Law of Thermodynamics: energy/matter can not be converted at 100% efficiency.

15. Think – Pair - Share How do you think the Laws of Thermodynamics will impact life?

16. So to get enough energy for the cells to work, we need atoms reacting together… Chemical reactions are the conversion (change) of substances from one form into another. (1 st Law of Thermodynamics) Follows the Law of Conservation of Matter This is the basic formula: Substrate  Product 2 things are necessary for a chemical reaction to occur 1)Substrates (Reactants) - what is being converted 2)Activation Energy – Energy for reaction to take place

18. Substrate + Enzyme  Product The products of a chemical reaction can either be larger (putting things together) or they can be smaller (breaking things down) than what we started with.

19. If we break down the original substance it is called a catabolic pathway. EX: H 2 O  H + H + O If we build up the original substances it is called anabolic pathway. EX: H + H + O  H2O

20. Think Pair Share Think of a mnemonic device to remember the catabolic and anabolic pathways.

21. Ion Formation

22. The pH Scale Measures H + concentration of fluid Change of 1 on scale means 10X change in H + concentration Highest H + Lowest H + 0---------------------7-------------------14 Acidic Neutral Basic Lowest OH- Highest OH-

23. Examples of pH Pure water is neutral with pH of 7.0 Acidic (Below 7.0) High % H+ – Stomach acid: pH 1.0 - 3.0 – Lemon juice: pH 2.3 Basic/alkaline (Above 7.0) High % OH- – Seawater: pH 7.8 - 8.3 – Baking soda: pH 9.0 – (buffers)

24. The pH Scale

25. Check your understanding: In terms of the math, what is the actual difference between a pH of 8 and 13? In terms of the chemistry, what is the difference between a pH of 8 and 13? What does the term “polar” mean? Where in an atom are each sub-atomic particle located? What things are needed for a chemical reaction to run? What is the name of all biological catalysts?