Important information about Organic Chemistry Reactions

1. Propose a mechanism for the entire reaction of 1-pentyne with HBr. Show why Markovnikov's rule should be observed in this addition.

2. Propose a mechanism for the entire reaction of 1-pentyne with HBr in the presence of peroxide.

3. When 2-pentyne reacts with mercuric sulfate in dilute sulfuric acid, the product is a mixture of two ketones. Give the structures of these products.

4. Draw the structure of the major product(s) formed when 2-pentyne is treated with a (i) cold, dilute solution of neutral potassium permanganate; (ii) warm, basic permanganate

5. Draw the structure of the major product(s) formed when 1-hexyne is subjected to ozonolysis, followed by hydrolysis.