Acids and Bases

What do acids react with?

metals

What gas is produced when acids react with some metals?

hydrogen

What do all acids contain?

hydrogen

CHARACTERISTICS of Bases:

• taste bitter & feel slippery

• pH greater than 7

• dissolves fat and oils

PROPERTIES of Bases

• Dissociate or ionize to form hydroxide ions (OH-) in water

• Proton acceptor

• Electron-pair donor

CHARACTERISTICS of Acids:

• sour tase and feels watery

• pH less than 7

• reacts w metals to form hydrogen gas

PROPERTIES of Acids

• Ionize to form hydronium ions (H3O+) in water

• Proton donor

• Electron-pair acceptor

What do acids and bases have in common?

both are corrosive and are electrolytes

Neutralization Reaction

acid + base —> salt + water

What is H₃PO₄ (phosphoric acid) used for?

• soft drinks

• fertilizer

• detergents

• dentistry

What is H₂SO₄ (sulfuric acid) used for?

• fertilizer

• car batteries

• rubber

What is HCl (hydrochloric acid) used for?

• stomach acid

• muriatic acid

What is HC₂H₃O₂ (acetic acid) used for?

vinegar & pickling

What is NaOH used for? (Bases)

• lye

• drain & oven cleaner

• soap making

What is Mg(OH)₂ used for? (Bases)

• laxative

• antacid

What is NH₃ used for? (Bases)

• cleaners

• fertilizer

• explosives

What is Ca(OH)₂ used for? (Bases)

• concrete

• soil stabilizer

Substances with a pH below 7 are [….]

more acidic

Substances with a pH above 7 are [….]

more basic

Indicators

substance that changes color in an acid or base

Acid-base indicators are very weak acids and bases that change color when they:

• accept a proton from acid

• donate a proton to a base

Litmus paper indicator: Color of acid & base

Acid — RED

Base — BLUE

Phenolphthalein indicator: Color of acid & base

Acid — COLORLESS

Base — PINK

Bromothymol blue indicator: Color of acid & base

Acid — YELLOW

Base — BLUE