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
state that, in general, ionic, covalent and metallic bonding are stronger than intermolecular forces
explain the variation in melting point and electrical conductivity in terms of the structure and bonding of the elements