Ch. 14

Acids & Bases

What's An Acid? An acid is any substance that increases

the H+ ion concentration in water. This causes the pH to drop They taste sour. They react with metals to make H2 gas

These are all the same thing:H+ H3O+ proton

The Six Strong Acids

• Dissociate completely in H2O

HCl H+ + Cl- (HCl is an Acid)

Ex: HCl – Hydrochloric AcidHBr – Hydrobromic Acid HI – Hydriodic Acid

H2SO4 – Sulfuric AcidHNO3 – Nitric AcidHClO4 – Perchloric Acid

Be Careful with Strong Acids

Weak Acids

These don’t completely dissociate in water.

Here is acetic acid, the one in vinegar: HC2H3O2(aq) H+

(aq) + C2H3O2-(aq)

about 99% about 1%

Some Strong and Weak Acids

What’s a Base?

Any substance that makes lots of hydroxide ions, OH-, in water.

They decrease the H+ ion concentration in water and increase the pH.

They taste bitter (ie: soap) and feel slippery

Strong Bases• They completely dissociate in water:

NaOH Na+ + OH-

•NaOH – Sodium Hydroxide•KOH – Potassium Hydroxide•LiOH – Lithium Hydroxide

•Ba(OH)2 – Barium Hydroxide

Be Careful with Strong Bases

Weak Bases

Don’t completely dissociate in water. Only about 1% to 5% is dissociated. Here is ammonia, a weak base:

NH3 + H2O NH4+ + OH-

Acids & Bases

Type Acid Base

Arrhenius H+ or H3O+ Producer

OH- Producer

Bronsted-Lowery

Proton (H+) Donor

Proton (H+) Acceptor

Lewis Electron-Pair

Acceptor

Electron-Pair Donor

Acid-Base Definitions

Acid Neutral Base

Neutralization Reactions

This is when you mix an acid with a base.

The result is always the same: Acid + Base Water + a Salt The salt can be any number of ionic

salts, not just NaCl.

Hydrochloric acid reacts with sodium hydroxide. Write the reaction:

HCl + NaOH H2O + NaCl

Before After

Another of Neutralization:

Sulfuric acid reacts with potassium hydroxide. Write and balance the reaction.

H2SO4 + 2KOH 2H2O + K2SO4

A Break & a Challenge: Say the color, not the word.