1. “CHEMISTRY OF LIFE” ATOMIC STRUCTURE

2. ELEMENTS: A SUBSTANCE THAT CAN NOT BE BROKEN DOWN INTO A SIMPLIER SUBSTANCE. ELEMENTS CONSIST OF ONE TYPE OF ATOM. These four elements make up 96% of living things c. 6 12.01 H 1 1.00 O 8 15.99 N 7 14.00 CARBON HYDROGEN OXYGEN NITROGEN

3. ATOMS: aTOm: Greek for “unable to be cut” Atoms are the building blocks of an element. Atoms consist of three sub-atomic particles: – Protons: Positively charged particles ( p+) – NEUTRONS: Particles with no charge (n°) – Electrons: negatively charged particles (e-)

4. ATOMIC SYMBOLS: Reading the atomic symbol Atomic Number = The Number of Protons and Also the Number of Electrons Atomic Mass = The Number of Protons Added to the Number of Neutrons The small # is always the Atomic Number & the larger # is always the Mass Number !

5. Fill In Chart Using Periodic Table Element SymbolAtomic # Atomic Mass p+n°e- Nitrogen Sodium Calcium Chlorine

6. Energy levels: Protons (p+) and neutrons (n°) Are located in the nucleus Electrons are located in Energy Orbitals outside of the nucleus *Ist Energy Orbital= 2e- *2 nd Energy Orbital= 8e- *3 rd Energy Orbital= 18e- *There is a “jumping” of e- between the 3 rd & 4 th Energy Level: We will fill using 2-8-8-18

7. OK….Let’s Practice! 96% of Your Body Is Made Up Of Four Elements on the Periodic Table: – C Carbon – H Hydrogen – O Oxygen – N Nitrogen Construct the Atomic Structure Diagram for Each of these elements! We will Do the First one Together On page 22 in your inb.

8. COMPOUNDS Substance composed of 2 elements chemically combined. Compounds form molecules. Example: +  SodiumChlorine Table Salt (NaCl)

9. COVALENT BOND Formed when 2 atoms share 1 or more pairs of electrons. Prefix Co- means with/together. Example: Water Hydrogen Atoms Oxygen Atom

10. COVALENT BONDS We will draw and label a molecule of water showing how Hydrogen bonds with Oxygen: Use Blue to represent Oxygen and Red to represent Hydrogen.

11. IONIC BONDS Combining of atoms by gaining or losing e- An atom that gains an e- becomes a negative ion An atom that loses an e- becomes a positive ion Importance of ions: Na+ and K+ are important for nerve functioning. Ca+ for muscle contraction

12. IONIC BONDS http://www.visionlearning.com/library/module _viewer.php?mid=55 http://www.visionlearning.com/library/module _viewer.php?mid=55 Sodium loses an e- so becomes a positive ion Chlorine gains an e- so it becomes a negative ion Sodium 11 p+ 11 e- Chlorine 17 p+ 17 e-