Naming

Question 1

SH group

Answer 1

Mercapto, when it’s a substituent

Question 2

SR group

Answer 2

A thiol. As a substituent it’s an alkylthio, as the stem it’s a thioalkane. It would be the substituent only if there’s a ring or an alcohol, which both have higher priority than anything else.

Question 3

Which comes first, ene or yne?

Answer 3

Whichever is closer to a terminus is numbered first, and the ene comes before the yne in the actual name because it’s alphabetically first

Question 4

E

Answer 4

alkene, top priority ones are on opposite sides. 3/4 substituents

Question 5

Z

Answer 5

alkene, top priority ones are on the same side. 3/4 substituents