Acids and Bases

What is an acid?

• Defined three ways:

– Arrhenius Acids: release H+ ions (protons) in aqueous solution.

– Bronsted-Lowry Acids: are proton donors.

– Lewis Acids: are electron pair acceptors

What is a base?

• Defined three ways:

– Arrhenius Bases: release OH- ions in aqueous solution

– Bronsted-Lowry Bases: are proton acceptors

– Lewis Bases: are electron pair donors.

Neutralization Reactions

• A neutralization reaction is an acid and base combining to form water

H+ + OH- → H2O

acid base neutral

acid base neutral

the pH scale

• The pH scale ranges from 0 to 14• 7 is neutral on the pH scale• Numbers below 7 are acidic– The acidity increases as the number decreases

• Numbers above 7 are basic– The basicity increases as the number increases

• The pH of a solution is exponentialpH= -log(H+)