Download More on Acids and Bases

More on Acids and Bases
Acids
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Acids are compounds that increase
the concentration of hydrogen ions
[H+] when they dissolve in water.
Acids solution have:
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pH below 7
Taste sour
Turn litmus paper red.
Bases
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Bases are compounds that increase
the concentration of hydroxide ions
[OH-] when they dissolve in water.
Bases have:
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pH greater than 7
Taste bitter
Feel slippery
Turn litmus paper blue
pH
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pH (0-14) measures the hydrogen
ion concentration in water.
Each pH unit involves a tenfold
change in hydrogen ion
concentration.
The pH number and the [H+] are
inversely related because
pH = - log [H+]
pH continued
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An increase of 1 pH unit means that
the hydrogen ion concentration has
decreased 10 times.
A decrease of 1 pH unit means that
the hydrogen ion concentration has
increased 10 times.
Arrhenius
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Arrhenius acids form hydrogen ions
in aqueous solutions
Arrhenius bases form hydroxide
ions in aqueous solutions.
Bronsted-Lowry
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Acids are proton donors
Bases are proton acceptors
Lewis
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Lewis Acids can accept a pair of electrons
Lewis Bases can donate a pair of
electrons
Strong Acids & Bases
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Both strong acids and bases dissociate
completely in water, and therefore are
strong electrolytes.
In a solution of a strong acid like
hydrochloric acid, almost all of the HCl
molecules dissociate:
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HCl  H+ + ClWhen 1 mole of HCl dissociates, it produces
2 moles of ions.
Weak Acids and Bases
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Weak acids and bases are weak
electrolytes and only partially dissociate..
In a solution of a weak acid like acetic
acid, only a few of the CH3COOH
molecules dissociate
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CH3COOH  H+ + CH3COOWhen 1 mole of CH3COOH dissociates it
produces LESS than 2 moles of ions because
only some of the molecules dissociate.
pH of weak Acids and Bases
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A 1 M solution of HCl would have a
LOWER pH than a 1M solution of
CH3COOH because HCl produces
more moles of H+ with its greater
degree of dissociation.
Acid Base Pop Quiz
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If the pH is 4 what is the pNeutral?
If the concentration of water is 30M,
then what is the ABC?
If the indicator was Hydronium,
what happened in the titration
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This quiz was a JOKE!!!
Next time, BE PREPARED FOR
CLASS!!!