Lecture 19.1a- Properties of Acids and Bases Acids taste sour, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution. 19.1

Acids taste sour, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution.

Citrus fruits contain citric acid. Tea contains tannic acid. 19.1

Citrus fruits contain citric acid.

Tea contains tannic acid.

Bases taste bitter, feel slippery, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution. 19.1

Bases taste bitter, feel slippery, will change the color of an acid-base indicator, and can be strong or weak electrolytes in aqueous solution.

Antacids use bases to neutralize excess stomach acid. The base calcium hydroxide is a component of mortar.

Antacids use bases to neutralize excess stomach acid.

The base calcium hydroxide is a component of mortar.

The Arrhenius definition of ACIDS AND BASES Acids dissociate to produce H + HCl  H + + Cl - Bases dissociate to produce OH - NaOH  Na + + OH -

H + and H 3 O + mean the same thing HCl  H + + Cl - Or HCl + H 2 O  H 3 O + + Cl -

H + is a proton Acids form H + which attaches to water forming the hydronium ion H + + H 2 O  H 3 O + hydronium ion

H + is a proton

Acidic hydrogens are written first in the chemical formula. HNO 3 = monoprotic acid H 2 SO 4 = diprotic acid H 3 PO 4 = triprotic acid HC 2 H 3 O 2 = monoprotic An acidic hydrogen can dissociate from the acid as H+.

Acidic hydrogens are written first in the chemical formula.

HNO 3 = monoprotic acid

H 2 SO 4 = diprotic acid

H 3 PO 4 = triprotic acid

HC 2 H 3 O 2 = monoprotic

An acidic hydrogen can dissociate from the acid as H+.

19.1 Acetic acid Stomach acid Battery acid In soda pop Vinegar Makes bubbles in carbonated beverages

Arrhenius Bases Hydroxide ions are one of the products of the dissolution of an alkali metal in water. 19.1

Arrhenius Bases

Hydroxide ions are one of the products of the dissolution of an alkali metal in water.

19.1

Milk of magnesia is a base used as an antacid.

Milk of magnesia is a base used as an antacid.

When acids and bases are mixed they react to form water in a Neutralization reaction NaOH + HCl  H 2 O + NaCl(aq) An acid/base reaction always forms water and an aqueous salt The net ionic equation for an acid/base reaction is H + + OH -  H 2 O

Neutralization reaction

NaOH + HCl  H 2 O + NaCl(aq)

An acid/base reaction always forms water and an aqueous salt

The net ionic equation for an acid/base reaction is H + + OH -  H 2 O

PROPERTIES OF ACIDS AND BASES ACIDS BASES Produce H + Produce OH - pH below 7 pH above 7 Sour taste Bitter taste H + + some metals = H 2 (g) Slippery feel Litmus paper red Litmus paper blue React with base to React with acid to form water and salt form water & salt BOTH ACIDS AND BASES ARE ELECTROLYTES

ACIDS BASES

Produce H + Produce OH -

pH below 7 pH above 7

Sour taste Bitter taste

H + + some metals = H 2 (g) Slippery feel

Litmus paper red Litmus paper blue

React with base to React with acid to

form water and salt form water & salt

BOTH ACIDS AND BASES ARE ELECTROLYTES