What factors should one look for when considering most acidic compound.?

For Organic Compounds, Acdity depends upon two Factors

• Anion Stability Effect

• Bond Strength effect

Anion Stability-More is the Anion Stability more is the acidity

Anion Stability Effect depends on a variety of factors like

• A compunds in which  the resulting anion is stabilised by resonance e.g phenoxide ion are more acidic than others
• -Inductive effects always increases acidity whereas the +Inductive effect always decreases acidity
•  Intramolecular hydrogen bonding in the compound results in decrease in acidity as ot stailises the acid
• A compund having the negative charge on more electronegative element is more acidic. H2O is more acidic than H2S

Bond Strength Effect-More is the bond strength less is the acidity

Bond Strength Effect depends on a variety of factors like

• In HF,HCl,HBr,HI , HI is the strongest acid as H---I is weakest among all.

However mostly anion stability effect is the most predominant factor in deciding the acidity. ond Strength effect is dominant only doing comparisons in a group.

For Inorganic Compounds, Acdity depends upon factors

• For Oxyacids

The compound in which the atom joined to Oxygen has the highest oxidation state is more stable than others

eg. among H2SO3 and H2SO4, H2SO3 is the weak one because in it the oxidation stae of sulphur is +4 whereas in h2so4 the oxidation stae is +6.

However the above concept doesn't applies to phosphorous acids