Older MCQs might not have the typical A, B, C,
D
choices. They
have choices 1, 2, 3, and a combination of them is the answer. Below is the key that maps such
combinations to the answer.
A
1, 2 and 3 are correct
B
1 and 2 only are correct
C
2 and 3 only are correct
D
1 only is correct
recall the reactions (reagents and conditions) by which aldehydes and ketones can be produced: (a) the oxidation of primary alcohols using acidified \( K_2Cr_2O_7 \) or acidified \( KMnO_4 \) and distillation to produce aldehydes (b) the oxidation of secondary alcohols using acidified \( K_2Cr_2O_7 \) or acidified \( KMnO_4 \) and distillation to produce ketones
deduce the possible isomers for an organic molecule of known molecular formula
recall the reactions (including reagents and conditions) by which alkenes can be produced: (a) elimination of HX from a halogenoalkane by ethanolic NaOH and heat (b) dehydration of an alcohol, by using a heated catalyst (e.g. \( Al_2O_3 \)) or a concentrated acid (e.g. concentrated \( H_2SO_4 \)) (c) cracking of a longer chain alkane
