(a) In group 1 because it has one valence electron in its outermost energy level. In group
(VII)
It lacks one electron to attain a duplet structure like group (VII) elements.
(b) Bond – covalent
Structure – giant atomic structure/giant covalent structure.
(c) B or C
(d) Alkaline earth metals
(e) (i) Atomic radius of B is larger than that of
Effective nuclear charge of E is greater than that of B.
(ii) Electrical conductivity of elements E and H
E is a good conductor /conductor has delocalized electrons .
H is non-conductor exists as a molecule (gas)
(f) (i) pH of solution of C is higher v 1than that of Sodium chloride solution of C is alkaline
while Sodium chloride solution is neutral
(ii) Used in street lights/fluorescent tubes/weather balloons /arc-welding
sharon kalunda answered the question on May 16, 2019 at 13:41
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