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
describe, in simple terms, the lattice structure of a crystalline solid which is: (a) giant ionic, including sodium chloride and magnesium oxide (b) simple molecular, including iodine, buckminsterfullerene \( C_{60} \) and ice (c) giant molecular, including silicon(IV) oxide, graphite and diamond (d) giant metallic, including copper
deduce the presence of a CH\(_3\)CH(OH)- group in an alcohol, CH\(_3\)CH(OH)-R, from its reaction with alkaline I\(_2\)(aq) to form a yellow precipitate of tri-lodomethane and an ion, \( RCO_2^-\)
deduce the presence of a CH\(_3\)CO– group in an aldehyde or ketone, CH\(_3\)CO–R, from its reaction with alkaline I\(_2\)(aq) to form a yellow precipitate of tri-lodomethene and an ion, \( RCO_2^-\)
