Chemistry · Periodicity in Elements
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Covalent character of hydrides decrease ________?
- A
Down the Group
- B
Across the Period
- C
Along the d-block
- D
All of these
The covalent character 'decreases in groups' as we go from top to bottom. Example in group 2, the hydrides of beryllium and magnesium are covalent, whereas the hydrides of strontium, calcium and barium are ionic. The covalent character decreases down the group as the electrons get further away from the nucleus. The attractive forces between the positive charge of the nucleus and negative charge of the electrons 'decrease' and it is easier to lose electron to hydrogen.
The covalent character decreases down the group as elements become larger, and their electrons are held less tightly by the nucleus, making the bonds more ionic.
Across a period, the covalent character does not consistently decrease; instead, it often increases due to higher electronegativity and smaller atomic radii.
The d-block elements show varied behavior in bonding due to partially filled d-orbitals, but the trend of decreasing covalent character is not applicable in the same straightforward manner as down a group.
The covalent character does not decrease across all mentioned trends; it specifically decreases down the group due to increasing atomic size and shielding effect.
Tagged under Chemistry · Periodicity in Elements · 2021