2. VSEPR: Electrons around an atom repel each other, and will move apart as far as possible to have space. The furthest away electrons can get in Carbon’s 4 bonds is 109.5 o apart. 109.5° The bond angles of carbon are 109.5°.

3. Carbon atoms in alkanes can rotate (twist) freely around each other. Multiple bonds restrict twisting or rotating.

4. Cis/Trans isomers Same formula - different arrangement of branches around the double bond. “cis” or “trans” shows different arrangement. Sometimes called - Geometric isomers 2-butene

5. Cis/Trans is possible only when each carbon in the double bond has a ‘bigger’ end between its other bonds. NOT every alkene has a cis or trans configuration. 2-butene

6. cis - largest alkyl groups on the same side of the double bond. cis-2-butene

7. trans - largest alkyl groups on opposite sides. trans-2-butene

8. 2-methyl-1-butene 4 3 21 DOESN’T have a bigger end on each carbon on the double bond – NO cis/trans

9. 3-methyl-2-pentene 5 4 3 2 1 cis-

10. Draw trans-4-octene: C - C - C C = C 45 6 7 8 1 2 3 C - C - C H H

11. Draw -4-ethyl-3-methyl-3-heptene: C - C - C C = C 2 4 5 6 7 1 C C - C CC - 3 cis