Home > Community > What is the relationship between hybridization and acidity or basicity?
Upvote

9

Downvote
+ Chemistry
Posted by
Aarij Asher

What is the relationship between hybridization and acidity or basicity?

Barbara Carlson  Follow

Increase in s character means more closer to the nucleus( s orbital is closer to the nucleus) . so it will lead to increase in its positive character. And this increases its electronegativity or electron gaining tendency. Thus increasing the acidic character or electron accepting character.

More

Upvote

VOTE

Downvote
Bob Sutterfield  Follow

Acidity means ability to donate proton and basicity to accept proton.These properties also relates to hybridization which involve mixing of s and p orbitals.Greater the s character greater the chances of proton donation thus greater the acidity.
For example,
H3C-CH3 has 25% s character, H2C=CH2 has 33.3% and HCCH is 50% ...so order of acidity is
HCCH>H2CCH2>H3CCH3
While the order of basicity increases with decrease in s character..

More

Upvote

VOTE

Downvote
Darshan Aryal  Follow

Sp has 50% S character and in sp2 has 33%.

Hydrogen attached to Alkyne(with 50%S) more acidic (and more electronegativy) than alkene.(with 33%S).

And hydrogen attached to alkene more acidic than alkane.(with 25%S).

More

Upvote

VOTE

Downvote
Azizi Gill  Follow

For acidity, the hydrogen should be attached to an electronegative atom. The more electronegative the atom is, the more acidic that hydrogen is.

Electronegativity depends on %s character. More the %s character, more the electronegativity of central atom. So, sp³ ordital has the least electronegativity and sp orbital is most electronegative.

Hence, it follows that alkynes (sp hybridised carbon) are more acidic than alkenes which are more acidic than alkenes.

The reason for this is that since the s orbital is spherical, electrons in it experience more force of attraction from the nucleus. Since electronegativity is largely associated by how tightly valence electrons are held, as s character of a hybrid orbital increases, it's electronegativity increases and hence its acidity increases.

Order of basicity is reverse order of acidity.

This result is realised when you'll know that Electronegativity of sp carbon is greater than that of sp³ nitrogen.

More

Upvote

VOTE

Downvote
Andrew Kiener  Follow

i think there is no relation between hybridization and acidity and basicity … but

HYBRIDIZATION. the mixing of different orbital of different shape . size and energy to give the set of new orbital of same shape . size and energy is know as hybridized orbital and the phenomena is called hybridization

but a little bit relation ship …. when sp hybridization in a molecule so it will be more acidic because s character increase the acidity of molecule….. when s character is more in a molecule so i will be more acidic and when s character is less in a molecule so it will be more basic speci….

More

Upvote

VOTE

Downvote