Alpha hydrogens and enolisable positions in drawn compounds

13 questions on Alpha hydrogens and enolisable positions in drawn compounds from the General Organic Chemistry III: Reaction Intermediates chapter: 2 NEET level, 5 JEE Main, 6 JEE Advanced. Each one opens with its answer and solution.

• Count the alpha hydrogens in the compound shown (hydrogens on carbons directly bonded to the carbonyl carbon). How many are there? NEET level, drawn structure
• The compound shown undergoes the Cannizzaro reaction, not the aldol reaction, with concentrated NaOH. Why? NEET level, drawn structure
• The compound shown is stirred with excess NaOD in D2O until exchange is complete. Assume that only hydrogens on carbons directly bonded to the carbonyl carbon e... JEE Main level, drawn structure
• A sample of the optically pure compound shown is stirred with aqueous NaOH. Which statement is correct? JEE Main level, drawn structure
• Which statements about the compound shown are correct? Select all that apply. JEE Main level, drawn structure
• Count the distinct enol forms of the compound shown, that is, constitutionally different enols obtained by enolisation toward each different alpha carbon. Do no... JEE Main level, drawn structure
• Count the distinct enol forms of the compound shown, counting E and Z geometrical isomers separately. How many are there? JEE Main level, drawn structure
• Consider only the mono-enol forms of the compound shown, in which one carbonyl group is converted into C=C-OH and the other stays as C=O. Counting E and Z isome... JEE Advanced level, drawn structure
• Which statements about the compound shown are correct? Count as alpha hydrogens those on carbons directly bonded to a carbonyl carbon. Select all that apply. JEE Advanced level, drawn structure
• The compound shown is stirred with excess NaOD in D2O until exchange is complete. Assume that every hydrogen on a carbon directly bonded to a C=O carbon or to a... JEE Advanced level, drawn structure
• The optically active compound shown is treated for a long time with aqueous NaOH. What happens to its optical activity? JEE Advanced level, drawn structure
• Which statements about the compound shown are correct? Count as alpha hydrogens those on carbons directly bonded to a carbonyl carbon. Select all that apply. JEE Advanced level, drawn structure
• Which statement about the compound shown is correct? JEE Advanced level, drawn structure