1. Draw the structure of cis-2-butene and give examples of the following terms based on this structure.

a) a pi bond

b) a sigma bond

c) a sp² hybrid orbital

d) a sp² hybrid orbital

e) bonds of 120 ^o

2. Draw the structures of one example each of compounds containing the following functional groups and that have the formula C₄H₈O.

a) Ketone

b) An aldehyde

c) An alkene

d) A cyclic ether

e) A cyclic alcohol.

3.Write the condensed structural formulas of the following compounds:

a) 3-chloropropyne

b) 2-methyl-3-ethylhexane

c) 2-butanone

d) 1,2-dibromoethane

4. Draw the structures of one example each of compounds containing the following functional groups and that have the formula C₄H₁₀O.

a) two different ethers

b) 5 alcohols (includes 2 optically active isomers)

5. Explain why there are two isomeric forms of 1,2 dibromoethene but only one form of 1,2-dibromoethane.