Trends in atomic radius
Chemistry discussion, revision, exam and homework help.
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Trends in atomic radiusTrends in atomic radius:
''As you move across a period, the nuclear charge increases. This means the electrostatic force of attraction between the positive nucleus and the negative outer electrons is stronger and therefore atomic radius decreases across a period.''
The electrostatic force of attraction refers to the force of attraction between the outer electrons and the nucleus right? Is this determined by the nuclear charge of the nucleus only, or are there other factors? -
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Re: Trends in atomic radiusIt's a balance between the nuclear charge and the shielding. There could be more protons in the nucleus, but if there's more shells between the nucleus and the outer electrons then the shielding will be higher and will outweigh the increase in nuclear charge, hence the nuclear attraction will be lower and the atomic radius will be higher.(Original post by sabre2th1)
Trends in atomic radius:
''As you move across a period, the nuclear charge increases. This means the electrostatic force of attraction between the positive nucleus and the negative outer electrons is stronger and therefore atomic radius decreases across a period.''
The electrostatic force of attraction refers to the force of attraction between the outer electrons and the nucleus right? Is this determined by the nuclear charge of the nucleus only, or are there other factors?
ETA: This explains why the atomic radius increases down a group. -
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Re: Trends in atomic radiusSo as the number of protons increases, the electrostatic forces of attraction between the nucleus and outer electron increases (as long as the shielding remains the same)? Thanks.(Original post by clownfish)
It's a balance between the nuclear charge and the shielding. There could be more protons in the nucleus, but if there's more shells between the nucleus and the outer electrons then the shielding will be higher and will outweigh the increase in nuclear charge, hence the nuclear attraction will be lower and the atomic radius will be higher.
ETA: This explains why the atomic radius increases down a group. -
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Re: Trends in atomic radiusExactly.(Original post by sabre2th1)
So as the number of protons increases, the electrostatic forces of attraction between the nucleus and outer electron increases (as long as the shielding remains the same)? Thanks.
This is the case as you go across a period.
