Answer
See explanation
Work Step by Step
a) First, draw the structure of 2-hexene. Draw 6 C in straight chain and numbering them from 1 to 6. Then, put a double bond between C2 and C3 carbon. remaining valency of C atoms is filled with H.
Now, look for the groups attached with the double bonded Carbon atoms. On one C atom, there are two groups attached i.e. methyl group and hydrogen. On another C atom, there are two groups attached i.e. propyl group and hydrogen. Cis isomer is formed when two same groups are on the same side.
b) First, draw the structure of 2-butene. Draw 4 C in straight chain and numbering them from 1 to 4. Then, put a double bond between C2 and C3 carbon. Remaining valency of C atoms is filled with H.
Now, look for the groups attached with the double bonded C. Both double bonded C atoms have two same groups attached i.e. methyl and Hydrogen. Trans isomer is formed when two same groups are oriented on the opposite side which can be seen above.
c) First, draw the structure of 2,3-dichloro-2-pentene. Draw 5 C in straight chain and numbering them from 1 to 5. Then, put a double bond between C2 and C3 carbon. Also, place two 'Cl' atom on C2 and C3 positions respectively.
Now, one double bonded C has two groups attached i.e. methyl and chlorine. Another double bonded C has two groups attached i.e. ethyl and chlorine. so, we have to draw the structure so that two Cl atoms are on the same side. That's how Cis isomer is mentioned.
