CH19 LAB: Properties of Acids & Bases

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Metal + Acid Salt + Hydrogen

LAB RESULTS

In the Lab:

Mg + 2HCl MgCl2 + H2

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Properties of Acids & Bases

• release hydrogen ions (H+) in solution

• neutralize bases • sour (acidus in latin means

sour) • turn blue and red litmus

paper red • turn phenolphthalein

colorless • pH= 0-6 • some are strong, some are

weak electrolytes • react with metals to

produce hydrogen gas 3

•release hydroxide ions (OH-) in solution •neutralize acids •bitter •turn blue and red litmus blue •turn phenolphthalein pink •pH= 8-14 •some are strong, some are weak electrolytes •have slimy, soapy feeling

Acids Bases

CH19: Acid & Base Naming Acids & Bases

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NAMING ACIDS

1. H 1st element in the formula 2. Next to H will be an anion (-) 3. The anion determines the name 4. There are two types of acids: • with oxygen • without oxygen

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NAMING ACIDS

1. Acids with no oxygen in the formula : Hydro + stem of 2nd element + ic + Acid Example: HCl H2S

HCl Hydrochloric Acid H2S Hydrosulfuric Acid

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NAMING ACIDS 2. Acids with oxygen in the formula (oxoacids)

“-ic” vs. “-ous”: If the polyatomic ion ends in “-ate” the acid ends in “-ic” “-ite” the acid ends in “-ous”

I ate acid and I got sic Last nite I was nauseous

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Hydrogen + central element + oxygen {polyatomic ion}

Stem of central element + ic + Acid Stem of central element + ous + Acid

EXAMPLES HNO3 HNO2 H2SO4 H2SO3 HClO3 HClO2

“-ic” vs. “-ous”: If the polyatomic ion ends in : “-ate” “-ic” “-ite” “-ous”

Nitric Acid Sulfuric Acid Chloric Acid

Nitrous Acid Sulfurous Acid Chlorous Acid

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I ate acid and I got sic Last nite I was nauseous

Practice

HF H3P HCN H2CrO4 HI

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Practice

HF Hydrofluoric Acid H3P Hydrophosphoric Acid HCN Hydrocyanic Acid H2CrO4 Chromic Acid HI Hydroiodic Acid

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WRITING FORMULA WHEN THE NAME IS GIVEN

1. Hydrogen will always be first 2. The name tells you the anion - “hydro”: monoatomic ions; no oxygen - “ic”: from polyatomic –ate - “ous”: from polyatomic –ite 3. Crisscross charges

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PRACTICE: Names & Formula

Hydroiodic acid Carbonic acid Hydrobromic acid Boric Acid Nitrous Acid Phosphorous Acid Acetic acid

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PRACTICE: Names & Formula

Hydroiodic acid Carbonic acid Hydrobromic acid Boric Acid Nitrous Acid Phosphorous Acid

HI H2CO3 HBr H3BO3 HNO2 H3PO3

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Acetic acid CH3COOH

PRACTICE: Names & Formula

Formic Acid Oxalic Acid Perchloric Acid Hypochlorous Acid Periodic Acid Iodic Acid Iodous Acid Hypoiodous Acid

HCOOH HOOC-COOH HClO4 HClO HIO4 HIO3 HIO2 HIO

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CH19 Naming Bases and Salts Review

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Naming Bases & Salts: Ionic Compounds

Metals: 1. Single charge: grp 1 (+1), grp 2,(+2) Al (+3),

Zn (+2), Ag (+1)

2. Multiple charges possible Write Roman numerals Ex: Cu+ (I) Cu2+ (II)

Nonmetals: 1. Polyatomic ions:

From the list you have

2. Monoatomic ions: stem + ide

Ionic Compounds: Metal + nonmetals Metal + polyatomic ions

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PRACTICE: Ionic Compounds

AgNO3 CaSO4 K2S Cu3N2

CaF2

Barium Hydroxide Zinc Carbonate Iron (III) Iodide Potassium Oxide

EX1: Li2SO4

EX2: AgCl EX3: PbCrO4

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CH19 Acid/Base Definitions

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ARRHENIUS DEFINITION [Acids]

HX- generic formula (X: monoatomic or polyatomic ion)

Ex: HNO3 H+ + NO3-

HCl H+ + Cl-

H2SO4 2H+ + SO42-

Produce hydrogen ions (H+) & Anions (X-) when dissolved in H2O

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ARRHENIUS DEFINITION [Bases]

Ex: NaOH Sodium Hydroxide KOH Potassium Hydroxide Mg (OH)2 Magnesium Hydroxide NH3 Ammonia- not a base

KOH K+ + HO

-

Produce hydroxide ions (OH--) & cations (X+) when dissolved in H2O

Why do bases conduct electricity when dissolved in water?

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ARRHENIUS DEFINITION [Salts]

Ex: NaCl sodium chloride KNO3 potassium nitrate MgBr2 magnesium bromide (NH4)2SO4 Ammonium sulfate

Products of acid-base reactions

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ARRHENIUS DEFINITIONS

Arrhenius

Definitions

ACIDS Produce [H+]

BASES Produce [OH-]

SALTS products of acid-base rxn K+ Cl-

OH- K+

H+ Cl-

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NEUTRALIZATION REACTIONS ACID + BASE SALT + H2O

Ex. HCl + NaOH NaCl + H2O Ex. HI + LiOH ____ + H2O Ex. HNO3 + Ca(OH)2 ____ + ____ Ex. H2S + LiOH Ex. H2CO3 + NH4OH ____ + ____ Ex. ____ + ____ MgSO4 + ____ Ex. ____ + ____ AlBr3 + ____

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