Acids - Bases – pH

Acids

• acids contain hydrogen ions (H⁺)

• a hydrogen ion is a hydrogen atom that has lost its valence electron and is actively seeking to get it back

Acid Characteristics

• sour taste (such as in fruit juices)

• corrosive (destroys body tissue and clothing)

• combine with bases to form salts

Acid Uses

• digestion (HCl acid)

• batteries

• production of paper, paint, detergent, and fertilizer

Bases

• bases contain hydroxide ions (OH^–)

• a hydroxide ion is compound with an extra valence electron and is actively seeking to give it away

Base Characteristics

• bitter taste (such as in soap)

• corrosive

• feels slippery

• combine with acids to form salts

Base Uses

• dissolve fats and oils

• drain cleaners

• antacids

• production of soap, cement, and fertilizer

pH Scale

• the pH scale measures how acidic or basic a solution is on a scale of 0 - 14:

• pH below 7 is acidic

• pH of 7 is neutral (water)

• pH above 7 is basic

Measuring pH

• pH is measured with litmus paper and pH paper by a change of color

• red indicates an acidic solution

• blue indicates a basic solution

• pH can also be measured by a direct reading computer probe

Remember

• Base, bitter, blue

• Acid, sour, red