Relative Acidity Etc

Electronegativity.  When comparing atoms within the same row of the periodic table, the more electronegative the anionic atom in the conjugate base, the better it is at accepting the negative charge

Size.  When comparing atoms within the same group of the periodic table, the easier it is for the conjugate base to accommodate negative charge (lower charge density). The size of the group also weakens the bond H-X (note this trend should be applied with care since it only works within a group).

Resonance.  In the carboxylate ion, RCO2- the negative charge is delocalised across 2 electronegative oxygen atoms which makes it more stable than being localised on a specific atom as in the alkoxide, RO-

2) Carboxylic Acid

1) Carboxcylic Acid

Carboxcylic Acid

Carboxcylic Acid

Phenol

Phenol

Phenol

Alchol

Alcohol

Amine

Inorganic

Sulfonic Acid

Alkene

Alkyne

Amine

H-H

Alkyne

Alkyne

Alcohol

Water

Positive Nitrogen

NH₄

Carboxcylic Acid

X-H

H₂SO₄

• F₃C-COOH
• Carboxcylic Acid with electronegative groups

• NH₄
• Has a positive charge on the nitrogen

HO < H2O < H3O

Increasing positive charge increases acidity

NH2 < NH3 < NH4

Increasing positive charge increases acidity

Methyl < Amine < Water < HF

Across the periodic table acidity increases with electronegativity

HF < HCl < HBr < HI

Dow the periodic table acidity increases with size.

Methanol < Phenol < Carboxcylic Acid

Stabilized through increasing resonance

C < A < B

Inductive effects of Br closer to OH

b < c < a

sp3 < sp2 < sp