Numbered Heads Together You work in group of 4. I will number you 1 to 4 I poses a question. 4. You each write the answer on a separate piece of paper that I give you 5. All 4 in the group then put their heads together to ensure all members can answer the question 6. I call a number and if you have this number, you share your group’s answers with the class.

1. Name:

1. Answer 1st branch 2 4-cyclobutyl-2-fluoro-6-methyloctane

2. Draw 2,5-dimethylhept-3-yne

2. Answer 2,5-dimethyl-3-heptyne

3. Identify the mistake in the following name 4-ethyl-2-methylpentane (hint: Draw out the molecule)

3. Identify the mistake in the following name- ANSWER 4-ethyl-2-methylpentane Longest chain is 6 C not 5C Correct name should be 2, 4- dimethylhexane

4. Which would have lower bp? Why?

4. Which would have higher bp? Why? Because it’s a more linear molecule even though it has fewer # of e-  better contact, stronger LD & pack better

Review DB geometry or No rotation around DB

Geometric isomers = cis/trans isomers Which is cis? trans? cis Because 2 chlorine on the same side of the C=C trans Because 2 chlorine on the opposite sides of the C=C

Could you name these with cis and trans?

Need another system: E Z system & a priority list Atom which has the higher atomic number is given the higher priority.

Geometric isomers: E Z system Zusammen (german) means together Entgegen means opposite (Z)- rest of name (E)- rest of name Z (zame): when 2 higher priortity groups on the Zame side of the DB E (enemies) : when 2 higher priority groups on opposite sides of the DB

E or Z? (E)-but-2-ene. E,Z will always work, even when cis,trans fails

4. Draw and name all geometric isomers of C3H3Cl3

4. All geometric isomers of C3H3Cl3 ANSWER (E)-1,3,3-trichloropropene (trans)-1,2,3-trichloropropene (cis)-1,2,3-trichloropropene (Z)-1,3,3-trichloropropene

5. List all the special properties of

5. Benzene special properties answer Flat molecule  efficiently stack/pack All C are sp2 hybridized Resonance structure Stable and non-reactive unlike alkenes Aromas Non-polar

6. Name:

6. Answer 1-chloro-2-isobutylbenzene Or o-chloroisobutylbenzene

Quiz Mon Apr 4 2016 Naming hydrocarbons: Aliphatic (non-cyclic & cyclic) Aromatic Know/able to explain their physical properties according their structure; draw all possible isomers including geometric isomers for alkenes