What are the conversions of: Alkene-alkane Alcohol-alkane Carboxylic acid-alkane, etc.?
Alkanes are the simplest organic molecules with a chain of carbons bonded by single bonds with hydrogens filling every remaining bond. Examples are methane, CH4, ethane, C2H6, propane, C3H8, and butane, C4H10. Other organic moelcules can be thought of as modfing this basic stable structure. Alcohols are produced by replacing one H with an OH group, usually at the end of the molecule. Methyl alcohol is CH3OH. We write the formula this way to clarify the structure. Ethyl alcohol, familiar from beer, wine, and sprirts, is C2H5OH. In the propane molecule we can put the OH either in the middle of the molecule or at one end. In the middle it produces isopropyl alcohol, or rubbing alcohol. Carboxylic acids are formed in a similar manner. Instead of an OH group we attach a carboxyl group COOH. Methy carboxylic acid is CH3COOH etc.
If we remove two H atoms and link two carbon atoms with a double bond we get alkenes. Ethene is H2C=CH2. We can remove two more H and replace the double bond with a triple bond in the midleto get alynes. HC+CH (+ stands for triple bond only in these notes) is called ethyne or more commonly acetylene.
Other classes of organic molecules such as amides, ketone, aldehydes, esters, and amines are similar variations of the basic structure of alkanes. Any standard chemistry book that goes into organic molecules will give you more detail.