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Why is acetylide anion more stable than benzyl anion?
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Luiz Gonzaga Medeiros
Why is acetylide anion more stable than benzyl anion?
The more s character the greater the ability to pull negative charge in toward the nucleus and stabilize it, This occurs because the s orbital has more electron density closer to the nucleus than the p orbital.
The acetylide anion is sp hybridized. That's 50% s character.
The benzyl anion is sp2 hybridized. That's 33% s character.
The reason why acetylene has a pKa of 25 and toluene has a pKa of 41 is that despite the delocalization of the benzyl anion, the benzyl anion has less s character than the acetylide anion does. (This is just another way of stating that the acetylide anion is more stable)
The more s character the greater the ability to pull negative charge in toward the nucleus and stabilize it, This occurs because the s orbital has more electron density closer to the nucleus than the p orbital.
The acetylide anion is sp hybridized. That's 50% s character.
The benzyl anion is sp2 hybridized. That's 33% s character.
The reason why acetylene has a pKa of 25 and toluene has a pKa of 41 is that despite the delocalization of the benzyl anion, the benzyl anion has less s character than the acetylide anion does. (This is just another way of stating that the acetylide anion is more stable)
Cation always loses electron giving itself a positive charge. So the positive charge means that the number of protons in the nuclues is greater than the number of electrons in the shells, giving ncleus an extra strength to attract the electrons tightly and thus decreasing its size.
But an anion gains electron attaining a negative charge. This negative charge gives an extra strength to the inner most electrons to shield themselves from the attraction of nucleus and thus anion is bigger in size than cation.
Or
In cation, due to loss of electrons the shells decrease and so does its size And in anion i would say vice versa.
Cation always loses electron giving itself a positive charge. So the positive charge means that the number of protons in the nuclues is greater than the number of electrons in the shells, giving ncleus an extra strength to attract the electrons tightly and thus decreasing its size.
But an anion gains electron attaining a negative charge. This negative charge gives an extra strength to the inner most electrons to shield themselves from the attraction of nucleus and thus anion is bigger in size than cation.
Or
In cation, due to loss of electrons the shells decrease and so does its size And in anion i would say vice versa.
The more s character the greater the ability to pull negative charge in toward the nucleus and stabilize it, This occurs because the s orbital has more electron density closer to the nucleus than the p orbital.
The acetylide anion is sp hybridized. That's 50% s character.
The benzyl anion is sp2 hybridized. That's 33% s character.
The reason why acetylene has a pKa of 25 and toluene has a pKa of 41 is that despite the delocalization of the benzyl anion, the benzyl anion has less s character than the acetylide anion does. (This is just another way of stating that the acetylide anion is more stable)
The more s character the greater the ability to pull negative charge in toward the nucleus and stabilize it, This occurs because the s orbital has more electron density closer to the nucleus than the p orbital.
The acetylide anion is sp hybridized. That's 50% s character.
The benzyl anion is sp2 hybridized. That's 33% s character.
The reason why acetylene has a pKa of 25 and toluene has a pKa of 41 is that despite the delocalization of the benzyl anion, the benzyl anion has less s character than the acetylide anion does. (This is just another way of stating that the acetylide anion is more stable)
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Cation always loses electron giving itself a positive charge. So the positive charge means that the number of protons in the nuclues is greater than the number of electrons in the shells, giving ncleus an extra strength to attract the electrons tightly and thus decreasing its size.
But an anion gains electron attaining a negative charge. This negative charge gives an extra strength to the inner most electrons to shield themselves from the attraction of nucleus and thus anion is bigger in size than cation.
Or
In cation, due to loss of electrons the shells decrease and so does its size And in anion i would say vice versa.
Cation always loses electron giving itself a positive charge. So the positive charge means that the number of protons in the nuclues is greater than the number of electrons in the shells, giving ncleus an extra strength to attract the electrons tightly and thus decreasing its size.
But an anion gains electron attaining a negative charge. This negative charge gives an extra strength to the inner most electrons to shield themselves from the attraction of nucleus and thus anion is bigger in size than cation.
Or
In cation, due to loss of electrons the shells decrease and so does its size And in anion i would say vice versa.
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VOTE