Formal Charge, Arrhenius, Bronsted Lowry

### Formal Charge

### Arrhenius Theory

* Acids - produce H+ when dissolved in H2O
* Bases - produce OH- when dissolved in H2O
* Weak - partially dissociates & Strong - completely dissociates

### Arrhenius Theory - Advantages & Limitations

Advantages

* explains strength of acids & bases
* properties of acids & bases in aqueous medium
* Neutralization reaction explained

Limitations

* only in aqueous medium not in gaseous medium
* can’t describe characteristics of compounds devoid of H+/OH-
* can’t explain acid-base reaction in absence of H2O

### Bronsted Lowry Theory

Acid - Donate proton

Base - Accept proton

### Bronsted Lowry Theory - ADV & DISADV

ADV

* Can explain in non aqueous medium
* basic character w/o OH- - NH3, CaO, Na2CO3
* acidic character w/o H+ - CO2, SO2
* acidic or basic nature of ionic species

DISADV

* can’t predict amphoteric gaseous molecules
* AlCl3, BF3, BCl3 - can’t loose or gain protons - hence can’t predict
* can’t explain reaction between acidic or basic oxides