EXAMS WITH QUALIFIED QUESTIONS
AND ANSWERS
How can an aldehyde be protected? - ANSWER-Using a diol and H+
What does permanganate do? (KMnO4, NaOH) - ANSWER-Oxidizes aldehydes and primary alcohols to
carboxylic acids
How can an acetal (being used as a protecting group) be hydrolyzed back to it's original form? -
ANSWER-H2O and H+ and heat
At what frequency is an OH or NH bond in IR spec? - ANSWER-3400
At what frequency is a CH (sp3) bond in IR spec? - ANSWER-3000-2850
At what frequency is a CH (sp2) bond in IR spec? - ANSWER-3100-3000
At what frequency is a CH (sp) bond in IR spec? - ANSWER-3300
At what frequency is a C-C triple bond or C-N triple bond in IR spec? - ANSWER-2100
At what frequency is C=O bond in IR spec? - ANSWER-1700
At what frequency is a C=C bond or aromatic C-C bond in IR spec? - ANSWER-1600
, At what frequency is an aromatic C-C bond in IR spec? - ANSWER-1500
At what frequency is carboxylic acid in IR spec? - ANSWER-1720 + a strong and broad band at 2500-3300
At what frequency is an amide bond in IR spec? - ANSWER-two medium strength bands around 3400 +
the carbonyl band below 1700
At what frequency is an sp3 C atom in a proton NMR spec? - ANSWER-1
At what frequency is a C atom attached to a pi system in a proton NMR? - ANSWER-2
At what frequency is a C atom attached to an O atom in a proton NMR? - ANSWER-3-4
At what frequency is an sp2 C atom in a proton NMR? - ANSWER-5-6
At what frequency is an aromatic C atom in a proton NMR? - ANSWER-7-8
At what frequency is an aldehyde C atom in a proton NMR? - ANSWER-10
At what frequency is a carboxylic O atom in a proton NMR? - ANSWER-11-12
At what ppm is an sp3 alkyl C atom in carbon NMR? - ANSWER-10-30
At what ppm is an sp3 C atom attached to O, N, or X in carbon NMR? - ANSWER-50-70
At what ppm is an sp C atom in carbon NMR? - ANSWER-75-90