QQuestion
Give a reason for each:
(a) Ionisation potential decreases down a group.
(b) Ionic compounds do not conduct electricity in the solid state.
✓Answer
(a) Down a group, atomic size and shielding increase; therefore the outer electron is held less strongly and is removed more easily.
(b) In a solid ionic compound, the ions are fixed in the crystal lattice and cannot move to carry electric current.
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