15 Acid Base Introduction

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The student will:
understand the concept of acids/bases.
will identify from a reaction strong/weak acid/base.
will be able to explain dissociation or ionization
and its relationship to strength of acid/base.
Will be able to identify a monoprotic, diprotic,
triprotic acid.
will be able to compare/ contrast pH of liquids
no ws
Acids
Vs. Base
What do lemons and pickles taste like?
Acids taste sour
Lemon, oranges, grapefruit = citric acid
Yogurt, sour milk = lactic acid
Carbonated drinks = carbonic acid
Vinegar = acetic acid
What does soap feel like?
Bases taste bitter
Soap = bitter
Shell of nuts = bitter
Acids & Bases do the same thing except from opposite directions
Acids & Bases
6 acids
Sulfuric
Nitric
Hydrochloric
Phosphoric
Carbonic
Acetic Acid
H2SO4
HNO3
HCl
H3PO4
H2CO3
HC2H3O2
What do you notice?
What makes an acid an acid?
Bases
Sodium Hydroxide
Magnesium Hydroxide
Aluminum Hydroxide
Potassium Hydroxide
Calcium Hydroxide
Barium Hydroxide
NaOH
Mg(OH)2
Al(OH)3
KOH
Ca(OH)2
Ba(OH)2
What do you notice?
What makes a base a base?
(OH) or the ability to make an (OH)
Ammonia
Sodium Hydrogen Carbonate
NH3
NaHCO3
Base solutions are sometimes called ALKALINE SOLUTIONS
H+
HCl + H20
Acids …
ionize themselves…
Back to Acids
+
Cl-
break apart into their ions.
Remember water is very polar
HCl + H20
H30+ + ClYou may see…either…..
H30+ or
These have names:
Hydronium ion,
hydrogen ion,
proton ion
H+
Back to Bases
Bases dissociate ….. Break apart producing hydroxide
NaOH + H20
NH3 + H20
Na+ +
NH4+ +
OHOH-
Which ion accounts for the alkalinity of
bases in water solutions?
1.
2.
3.
4.
Hydronium ion
Sodium ions
Hydroxide ions
Alkali metals
Which of the following is an alkali?
1.
2.
3.
4.
Mg(OH)2
H2SO4
HCl
ZnCO3
Before
ionization
After
ionization
HAcid
H+
A-
HAcid
H+
W
Strong
Acid
Weak
Acid
H+
B-
Contents of solution
Strong vs. Weak
Can tell 2 ways
memorize them
arrows
Strong acids:
HCl, H2SO4, HNO3
Weak acids:
H2CO3, HC2H3O2, H3PO4
Strong Base:
group 1, 2 metals
Weak base:
NH3
ionize completely
dissociates completely
HF + H20
H2SO4 + H20
F- + H30+
HSO4 + H30+
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
The ease with which the hydrogen to the element bond can be broken
Strong acids= HCl, HNO3, H2SO4
Weak Acid = H3PO4, H2CO3, HC2H3O2
Notice: strength of acid does not depend on number of hydrogens
Strength of bases
depends on:
OH- production
polarity of bonds
dissociation of hydroxide
Base solutions are sometimes called
alkaline solutions
Strong Bases: NaOH, KOH, Ca(OH)2, Ba(OH)2
Weak Base: NH3
According to the dissociation
theory, the ion present in all basic
solutions is…
1.
2.
3.
4.
O-2
OHH3O-1
OH-2
The term strong and weak refer to…
1.
2.
3.
4.
5.
The concentration of the electrolyte.
The degree of ionization
The amount of solvent
The number of electron pairs
The number of hydrogens
Monoprotic
Diprotic
Triprotic
HCl,
H2SO4,
HNO3
H3PO4,
H2CO3,
HC2H3O2
Return to strength of Acid/Base
Memorize list -- look at arrows -- measure the pH.
What makes an Acid an Acid?
What makes a base a base?
H30+
Pure water is neutral
pH = 7
“self- ionizes”
OH-
Water molecule + water molecule = hydronium ion + hydroxide ion
Neutral because equal number of hydronium and hydroxide( ½ ½ )
pH scale
Power of the hydrogen
pH scale measures:
the concentration of the hydromium ion or hydroxide ion.
pH = 0…..14
0
3
Units of 10
Ph paper/ instruments
7
10
14
The will student will:
understand the concept of acids/bases
will identify from a reaction strong/weak acid/base
will be able to explain dissociation or ionization
and its relationship to its strength.
Will be able to identify a monoprotic, diprotic,
triprotic acid
will be able to compare/contrast pH of liquids
no ws
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