CHAPTERS 19 CHAPTERS 19

ACIDS & BASESACIDS & BASES

What do you see?

Acid PropertiesAcid Properties Sour taste (citrus fruits)Sour taste (citrus fruits) Conduct electric currentConduct electric current Change the color of indicators-turns litmus paper redChange the color of indicators-turns litmus paper red pH concentration < 7pH concentration < 7 React with bases to produce salt and water:React with bases to produce salt and water:

HCl + NaOH HCl + NaOH H H22O + NaClO + NaCl

Some react with metals to release HSome react with metals to release H22 gas: gas:Mg + HCl Mg + HCl MgCl MgCl22 + H + H22

Naming AcidsNaming Acids

1.1. Binary Acids: Binary Acids: a. Ha. H22SS hydrohydrosulfuric acidsulfuric acid

2.2. Ternary Acids: Ternary Acids: a. Ha. H22SOSO44

- - ““ICIC II ATEATE thatthat” ” sulfursulfuric ic acidacid

b. Hb. H22SOSO33

-“-“RRITEOUSITEOUS” ” s sulfurulfurous ous acidacid

Base (alkaline)Base (alkaline)PropertiesProperties

Bitter taste (coffee)Bitter taste (coffee) Feel slippery (soap)Feel slippery (soap) Change the color of indicators-turns litmus Change the color of indicators-turns litmus

paper bluepaper blue Caustic- attack the skin, cause severe Caustic- attack the skin, cause severe

burnsburns Conduct electric currentConduct electric current

Arrhenius Acids and BasesArrhenius Acids and Bases Arrhenius AcidArrhenius Acid: : A compound that produces HA compound that produces H++ in solution. Ionizes to in solution. Ionizes to

yield a proton in an aqueous solution.yield a proton in an aqueous solution.

Ex:Ex: HHCl (g) --------Cl (g) -------- HH++ (aq) + Cl (aq) + Cl- - (aq)(aq)

Arrhenius BaseArrhenius Base: : A compound that produces OHA compound that produces OH-- in solution. in solution.

Ex: NaEx: NaOHOH (s) --------- (s) --------- Na+ (aq) + Na+ (aq) + OH-OH- (aq) (aq)

H2O

H2O

Hydronium ionHydronium ion

The particle formed by the combination of a The particle formed by the combination of a hydrogen ion with a water molecule.hydrogen ion with a water molecule.

HH+ + + H+ H22O O HH33OO+1+1

pH ScalepH Scale A more convenient way to A more convenient way to

express acidityexpress acidity

pH = -log[HpH = -log[H33OO++]] pOH = -log[OH-]pOH = -log[OH-] pH + pOH = 14.0pH + pOH = 14.0

Find the pH and pOH of a 1x10Find the pH and pOH of a 1x10-10-10 M M solution of HBr. solution of HBr.

1. HBr is an acid so we are looking at the 1. HBr is an acid so we are looking at the [H[H++] concentration.] concentration.

[H[H++] = 1x10] = 1x10-10-10 M M

2. pH = -log[1x102. pH = -log[1x10-10-10]]pH = 10pH = 10

3. pH + pOH = 143. pH + pOH = 14 10 + pOH = 1410 + pOH = 14 pOH = 4pOH = 4

pHpH

pH 0-7: acidic solutionpH 0-7: acidic solutionpH 7: neutral solutionpH 7: neutral solutionpH 7-14: basic solutionpH 7-14: basic solution

Calculating pHCalculating pHpH = -log [HpH = -log [H++]]

Ex: A solution has a HEx: A solution has a H++ concentration of 1x10 concentration of 1x10-5-5

pH = -log [1x10pH = -log [1x10-5-5]]pH = 5 and we have an acidic solutionpH = 5 and we have an acidic solution

Ex: A solution has a pH=8Ex: A solution has a pH=88 = -log [H8 = -log [H++]][H[H++] = 1 x 10] = 1 x 10-8-8