Acids

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Acids Bases chapter15

• 6 acids
• Sulfuric H2SO4
• Nitric HNO3
• Hydrochloric HCl
• Phosphoric H3PO4 cola
• Carbonic H2CO3
• Acetic Acid HC2H3O2 vinegar
• What do you notice?
• What makes an acid an acid?

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• HCl H20 H Cl-
• Acids ionize themselves break apart into
  their ions.
• Remember water is very polar
• H20 HCl H30 Cl-
• You may seeeither.. H30 or H
• These have names hydronium ion, ,
  hydrogen ion, , proton ion.

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• Bases
• Sodium Hydroxide NaOH
• Magnesium Hydroxide Mg(OH)2
• Aluminum Hydroxide Al(OH)3
• Ammonia NH3
• Sodium Hydrogen Carbonate NaHCO3
• What do you notice?
• What makes a base a base? (OH) or the ability to
  make an (OH)
• Base solutions are sometimes called ALKALINE
  SOLUTIONS
• Bases dissociate .. Break apart producing
  hydroxide
• NaOH H20 Na OH-
• NH3 H20 NH4 OH-

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Strong vs. Weak p.460 p. 469

• Can tell 2 ways memorize them
• arrows
• HX H20 H30 X- label
• Strong acids HCl, H2SO4, HNO3 ionize
  completely
• Weak acids H2CO3, HC2H3O2, H3PO4
• Strong Base group 1 or 2 metal hydroxides
• Weak base NH3 dissociates completely

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• HF H20 F- H30
• H2SO4 H20 HSO4 H30

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• Strength of acids
• depends on H production
• polarity of bonds
• ionization
• The greater the polarity of bond greater
  strength
• The greater the ionization greater strength
• Strong acids HCl, HNO3, H2SO4
• Weak Acid H3PO4, H2CO3, HC2H3O2
• Notice strength of acid does not depend on
  number of hydrogens

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• Strength of bases
• depends on OH- production
• polarity of bonds
• dissociation of hydroxide
• The greater the polarity of bond greater
  strength
• The greater the dissociation greater strength
• Base solutions are sometimes called alkaline
  solutions
• Strong Bases NaOH, KOH, Ca(OH)2, Ba(OH)2
• Weak Base NH3
• Note Alkali metals are stronger than alkaline
  earth.why?
• Strong Acid/ Strong Base Strong
  electrolyte..why?

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pH Scale pH measures concentration of H30
or OH-

• pH .. O 14
• 0 3 7 10 14
• Units of 10
• 4.6 pH is 10x stronger than 5.6pH
• 4.6 pH has 10x H30 than 5.6 pH
• Pure water is neutral..pH 7
• self-ionization of water
• Water produces ½ H and ½ OH-

H
OH-
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20 minute lab
Red litmus paper turns blue in base Blue litmus
paper stays blue in base Determine pH using the
rainbow chart
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pH H30 or H pH power of the Hydrogen

• Calculating pH from concentrations
• pH -log H3O
• pOH -log OH-
• pH pOH 14
• ws.17.24
• Calculator
• number exponent
• Find pH of a solution of hydronium concentration
  of 3 x 10-5?
• pH -log 3 x 10-5
• 3
  -5

Yellow 2nd
(-)
log
EE
Yellow 2nd
(-)
log
EE
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• 1 x 10-3 M HCl
• 1 x 10-5 M HNO3
• 0.001 M HCl
• 0.09 M HBr
• 1.34 x 10-4M HCl
• 7.98 x 10-2 M HNO3

Calculate pH
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• pH pOH 14
• ph pOH
• 2 14
• 8 14
• 6 14
• 13 14
• 4 14
• 7 14

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• Find the pH of a solution of Hydroxide
  concentration of 3 x 10-5
• (-)log 3 -5
• BUT it is hydroxide so..it is the pOH.so
  subtract it from 14.

Yellow 2nd
EE
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• Calculate pH
• 1 x 10-4 M NaOH
• 1 x 10-3 M KOH
• 1 x 10-6 M LiOH
• 3.2 x 10-2 M Mg(OH)2
• 0.08 M Ca(OH)2

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• Calculate pH
• Hydronium concentration of .001M
• Hydroxide concentration of .001 M
• H concentration of 1 x 10-5 M
• OH concentration of 1 x 10-5 M
• Ws.14.1

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• Ws.17.26
• A popular soda pop drink is measured to have a
  hydronium concentration of 1.34 x 10-4. What is
  the pH and is it acidic, base or neutral?
• The molarity of hydroxides in a pancake syrup is
• 1.0 x 10-8M. Pancake syrup by law must have a
  pH lower than 7 to be sold in the open market.
  Calculate the pH and identify if acid, base,
  neutral. Can it be sold?

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• 3. You work for Colgate Toothpaste. You need
  to make stannic fluoride solution of hydroxide
  molarity 2.44 x 10-4. What is the ph? Is it
  acid, base, neutral?

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• If pH is 7.40 what is the hydronium or the
  molarity?
• If given pHfind antilog
• negative hydronium conc.
• -7.40 .00000004 or 4 x 10-8
• secret.hydronium concentration is the molarity
  
• BUT if they also ask for hydroxide
  concentration one must use the equilibrium
  constant for water
• Equilibrium Constant for water is
• Kw H OH-
• Kw 1 x 10-7 1 x 10-7
• Kw 1 x 10-14

Yellow 2nd
log
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1. The pH of an orange is 4.0pH. What are the H30
   and OH in this fruit? What is its Molarity?
2. Lemons have a pH 3.15. What are the hydronium
   and the hydroxide concentrations? What is its
   molarity?

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1. What is the molarity of pH is 12.9 for a Calcium
   hydroxide solution?

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• Remember 3 formulas pH-logH3O
• pOH-logOH
• pH pOH 14
• Remember H3O is hydronium concentration
• or..molarity for an Acid
• or..H proton concentration
• Remember OH is hydroxide concentration
• or molarity for a base
• Remember if given pH use antilog to calculate
  H3O OH
• put pH in as negative number
• Remember Kw H3O OH 1x10-14
• Kw 1x10-7 1x 10-7
• Kw 1x10-14

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Neutralization Reaction

• p.474
• Strong acid Strong Base salt water
• Look on reference table 4c
• HCl H20 H Cl-
• NaOH H20 OH- Na
• Put them together
• HCl NaOH NaCl H2O
• Salt a compound composed of
• a cation from an base
• and an anion- from a acid.

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• Stomach Ache
• CaCO3 .tums
• HCl Mg(OH)2 milk of magnesia
• NaCO3 . Rolaids
• Neutralize ..salt H20
• HCl CaCO3 CaCl CO2 H20
• HCl Mg(OH)2 MgCl H20
• HCl NaCO3 NaCl CO2 H2O
• Which will make you burp?
• Tums and Rolaids that is why old people prefer
  milk of magnesia

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• Titration
• the controlled addition and measurement of
• the amount of a solution of known concentration
• required to react completely with a
• measured amount of a solution of unknown
  concentration p.497
• Equivalence point The point at which the two
  solutions used in a titration are present in
  chemically equivalent amounts p. 498
• Indicator an organic substance that changes
  color whether in acid or base.Phenolphthalein

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• Calculating Titration Problems ws 19-3
• On your reference sheet nM1V1 nM2V2
• n of (H) or (OH) in the molecule
• Ws 19-3
• 1. A volume of 30mL of 0.25M HCl neutralizes a
  50mL sample of KOH solution. What is the
  concentration of KOH? Create new copyrght

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• 6. A volume of 50mL of 0.30M HCl neutralizes a
  60mL sample Ca(OH)2 solution. What is the
  concentration of Ca(OH)2?

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2 acid / base theories

• Arrhenius acids bases p. 459
• Arrhenius acid a chemical that increases H
  ions.
• Arrhenius base a chemical that increases OH-
  ions
• limited because must be in water.not everything
  in water..p.464
• Bronsted-Lowery acids bases p.464
• Bronsted-Lowery acid a chemical that is a
  proton donor (H)
• Bronsted-Lowery base a chemical that is a
  proton acceptor (H)
• notice no mention of OH

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Conjugate acid/ base the species that forms in
result of gaining or losing a proton (H)

• acid base
• Arrhenius Hdonor OH- producer
• Bronsted-Lowery Hdonor H acceptor
• Overhead worksheet 15.2,3,, 15.4

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• Overhead 88 , 87 quick lab
• Remember Equilibrium Keq conc conc
• .(g) and (aq) but not liquids nor solids
• Equilibrium Constant for water is
• Kw H OH-
• Kw 1 x 10-7 1 x 10-7
• Kw 1 x 10-14
• On chemistry table.constant like.. pie 3.14
• r .0821
• We can use this constant
• (Kw 1 x 10-14) to calculate pH of a solution
• Ws problems 17.

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