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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