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ACIDS
An acid -------> H+ in water
Strong acids (dissociate 100%) are…
HCl
H2SO4
HClO4
HNO3
HBr
HI
hydrochloric
sulfuric
perchloric
nitric
hydrobromic
hydroiodic
HNO3
A SAMPLE
Aqueous sodium hydroxide is added to sulfuric acid…
NaOH(aq) + H2SO4(aq)
NaHSO4 + HOH
NaOH(aq) + H2SO4(aq)
NaHSO4(aq) + HOH(l)
Na++OH- + H+ +HSO4Na+ + HSO4- + HOH
OH- + H+
HOH
ACIDS An acid -------> H+ in water
HCl(aq) ---> H+(aq) + Cl-(aq)
Strong Acids in water, actually release the
H+ ion which forms H3O+ (the hydronium
ion)
The Nature of Acids
HCl
H2O
Cl-
hydronium
ion
H3O+
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Weak Acids
Some WEAK ACIDS = weak
electrolytes(do not dissociate 100%)
Write them as molecular (do not break up)
CH3CO2H or HC2H3O2 acetic acid
H2CO3
carbonic acid
H3PO4
phosphoric acid
HF
hydrofluoric acid
ACIDS
Nonmetal oxides can be acids
CO2(aq) + H2O(l) ---> H2CO3(aq)
SO3(aq) + H2O(l) ---> H2SO4(aq)
and can come from burning coal
and oil.
BASES
Base ---> OH- in water
NaOH (aq)
---> Na+ (aq) + OH- (aq)
NaOH is a strong base
Strong Bases dissociate 100% in
water
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BASES
CaO(s) + H2O(l)--> Ca(OH)2(aq)
STRONG BASES
NaOH & KOH & LiOH
{all group 1A hydroxides are
strong bases although not all
are common in the lab}
CaO in water. Indicator
shows solution is basic.
Ca(OH)2, Ba(OH)2 and
Sr(OH)2 are also strong bases
Weak acid and strong base
Write the molecular, ionic and net ionic
equation for phosphoric acid reacting with a
solution of potassium hydroxide.
Acids dissociate one hydrogen at
a time
Molecular equation
H3PO4 + KOH  KH2PO4 + HOH
To finish…
H3PO4 + KOH  KH2PO4 + HOH
Decide what the physical state are of the products
H3PO4 + KOH  KH2PO4(aq) + HOH (l)
The ionic equation…
H3PO4 + K+ + OH-  K+ + H2PO4- +HOH
The net ionic equation…
H3PO4 + OH-  H2PO4- +HOH
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