Are bonds formed in higher energy levels weaker?

AI Thread Summary
In the discussion about the strength of bonds in the 2p versus 3p subshells, it is noted that there is no definitive rule governing their relative strength, especially in the context of excited atoms forming excimer molecules. The conversation highlights that as one moves down a group in the periodic table, the first ionization energy generally decreases due to an increase in atomic radius and the number of occupied energy levels, which weakens the electrostatic attraction between valence electrons and the nucleus. Conversely, moving across a period results in an increase in first ionization energy due to a decrease in atomic radius and an increase in effective nuclear charge, enhancing the attraction between valence electrons and the nucleus. The discussion also touches on the nature of bonds formed by group three elements, suggesting that bonds involving higher energy level electrons may be weaker due to expanded octets and increased electron repulsion, leading to smaller bond angles in certain geometries.
TT0
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If there was a bond in the 2p vs 3p subshell, which would be stronger? Taking into consideration that they are in the same group

Thanks
 
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There is no general rule that I am aware of. In some cases, you can only for molecules with excited atoms: excimer molecules.
 
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I see, thanks. But then when you move down a group, doesn't the ionisation energy increase? Or am I mixing two different things?
 
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TT0 said:
I see, thanks. But then when you move down a group, doesn't the ionisation energy increase? Or am I mixing two different things?
Quite the opposite really, moving down a group the general trend is 1st ionisation values tend to decrease; this is explained by the increase in the number of occupied energy levels causing an increase in atomic radius, therefore electrostatic attraction between valence electrons and the nucleus is weaker. Hence, 1st I.E values decrease moving down a group as the atom requires less energy to be ionised and overcome the electrostatic attraction.

However, moving across a period 1st ionisation energy does increase as atom radius decreases; this is explained by the increase in effective nuclear charge (Zeff), therefore the valence electrons experience greater electrostatic attraction with the nucleus. Hence, 1st I.E values increase across a period as the atom requires greater energy to be ionised and overcome the electrostatic attraction.

Thought I might write this to help elucidate your question, hope it helps.

Yes, I suppose bonds made with electrons in higher energy levels are weaker as group three elements have expanded octets and thus can form more than the expected number of covalent bonds with other atoms. As a result, the electrostatic attraction could be weaker due to greater repulsion; this is probably explained by their smaller bond angles as electron domains form the greatest angles possible between one another to minimise repulsion. Hence, covalent compounds with trigonal bipyramidal and octahedral e- domain geometries tend to have smaller bond angles between electron domains compared to tetrahedral geometries, due to an increase in repulsion. This is just my guess.
 
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I see thanks mate
 
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