Acids and Bases

Properties of Acids Acidus – meaning sour or tart Feels like water Litmus Paper – red Conducts electricity Reactive with metals React with bases to form a salt and water

Properties of Bases Bitter taste Feels smooth and slippery (soap) Litmus Paper – Blue Conducts electricity Not reactive with metals React with acids to form a salt and water

Common Acids Formula Name HCl Hydrochloric acid HNO3 Nitric Acid H2SO4 Sulfuric Acid HC2H3O2 Acetic Acid H2CO3 Carbonic Acid H3PO4 Phosphoric Acid

Common Bases Formula Name Na(OH) Sodium Hydroxide K(OH) Potassium Hydroxide Mg(OH)2 Magnesium Hydroxide Ca(OH)2 Calcium Hydroxide Sr(OH)2 Strontium Hydroxide

Names of Acid/Base Ions H+ H3O+ OH-

Arrhenius Acid Acid: substance that produces hydrogen ions (H+) or hydronium ions (H3O+) in water H+ = H3O+ THEY ARE THE SAME THING!! Example: HCl + H2O  Cl- + H3O+

Arrhenius Base Base: substance that produces hydroxide ions (OH-) in water Example: Na(OH)  Na+ + (OH)-

Monoprotic Acids Polyprotic Acids monoprotic acid : acid that can donate only one proton (hydrogen ion) per molecule. Example: HCl, HNO3 polyprotic acid : acid that can donate more than one proton per molecule. Examples: H2SO4 - diprotic H3PO4 - triprotic Polyprotic Acids

Monoprotic and Diprotic Acids

pH Calculations

To measure the concentration of these ions produced we use pH Ionization of Water Experiments have shown that pure water, at 25°, breaks apart (ionizes) : H20 + H20 H30+ + OH- To measure the concentration of these ions produced we use pH

pH Scale Acidic Basic NEUTRAL pH [ H+ ]=10-7 M=[OH- ] pH = 7 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 Acidic Basic NEUTRAL pH [ H+ ]=10-7 M=[OH- ] pH = 7 More acidic More basic

Relationship of [H3O+] to [OH–]

pH - from the Danish: “power of Hydrogen” The pH Scale pH: scale used to indicate the [H+] of a water solution pH - from the Danish: “power of Hydrogen” pH = - log [H+] or pH = - log [H3O+]

pH = - log [H+] The log function converts the exponents with a base of 10 to a whole number. The negative sign at the front of the equation cancels out with the negative sign in the exponent. [H+]: 100 10-1 10-2 10-3 10-4 10-5 10-6 10-7 10-8 10-9 10-10 10-11 10-12 10-1310-14 pH : 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14

pH Practice 10-2 2 Acid 10-8 10-5 10-7 13 [H+] Concentration pH Acid, Base, or Neutral? 10-2 2 Acid 10-8   10-5 10-7 13

Acids/ bases Oven cleaner Surface Cleaner Detergent Coffee Soda

Acid Base Reactions

Neutralization Reactions forms salt forms water neutralization: when an acidic solution (with hydrogen ions) and a basic solution (with hydroxide ions) react to form water salt: an ionic compound formed from the cation of a base and an anion of an acid.

Neutralization Reactions

Buffer Solutions A solution that resists changes in pH What are some solutions that need to maintain a certain pH level? Blood, stomach acid (antacids), pools

Acid Rain NO, NO2, CO2, SO2, and SO3 are gases from industrial processes that dissolve in atmospheric water to produce acidic solutions. Example: Very acidic rain is known as acid rain.

Why is acid rain dangerous?

Why is acid rain dangerous?