Acids and Bases
Acids
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Sour taste
Conduct electricity
React with metals to produce H2(g)
React with carbonates to produce CO2(g)
React with bases to produce water and a salt
Turn blue litmus red
Are formed when non-metal oxides react with
water. e.g. CO2 + H2O  H2CO3(aq)
Identifying Acids
• Usually the name of an acid ends with the
word “acid”
• The chemical formula starts with the symbol
for hydrogen (H) and ends in (aq) (e.g. HCl(aq))
or
• The chemical formula ends with COOH (the
symbol for the carboxyl polyatomic ion) and
ends in (aq) (e.g. CH3COOH(aq))
Naming Acids
• We will use two general rules for naming acids in
this course:
I. Binary Acids:
Starts with H and has only one other non-metal:
1. Start with the prefix “hydro”
2. Change the ending of the non-metal to “ic” and
add the word acid.
e.g. HCl(aq)
- hydrochloric acid
HF(aq)
- hydrofluoric acid
HBr(aq)
- hydrobromic acid
HI(aq)
- hydroiodic acid
H2S(aq)
- hydrosulfuric acid
II. Oxy-Acids: Starts with H and contains a
polyatomic ion that ends in “ate”.
1. Start with the name of the element in the
polyatomic ion that is not oxygen.
2. Change the element’s ending to “ic” and add
the word “acid”
e.g. H2SO4(aq) - sulfuric acid
H3PO4(aq) - phosphoric acid
HNO3(aq) - nitric acid
H2CO3(aq) - carbonic acid
HClO3(aq) - chloric acid
Common Acids
HCl(aq) – hydrochloric acid
(muriatic acid, stomach acid)
H2SO4(aq) – sulfuric acid
(battery acid)
HCOOH(aq) – methanoic acid
(formic acid)
CH3COOH(aq) – ethanoic acid
(acetic acid)
Bases
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Bitter taste
Conduct electricity
Feel slippery
React with acids to produce water and a salt
Turn red litmus blue
Are formed when metal oxides react with
water. e.g. NaO + H2O  NaOH(aq)
Identifying Bases
• Usually the name begins with the name of a
metal ion or ammonium and ends with the
word “hydroxide” or “carbonate”
• The chemical formula starts with a metallic ion
or with the ammonium ion (NH4+)
AND
• The chemical formula ends with OH- or CO32-
Naming Bases
• The name of a base can be determined by its
chemical formula.
1. Write the name of the positively charged metal
ion or positively charged polyatomic ion that is
at the beginning of the chemical formula.
2. Add the word “hydroxide” or “carbonate” at the
end (depending on which is there)
e.g. KOH(aq)
- potassium hydroxide
NH4OH(aq) - ammonium hydroxide
CaCO3(aq) - calcium carbonate
Common Bases
• NaOH(aq) – sodium hydroxide
(caustic soda, lye)
• NH4OH(aq) – ammonium hydroxide
(ammonia solution)
• Ca(OH)2(aq) – calcium hydroxide
(slaked/hydrated lime)
• Mg(OH)2(aq) – magnesium hydroxide
(milk of magnesia)
• NaHCO3(aq) – sodium bicarbonate
(baking soda)
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Acids and Bases in the Body
Neutralization Reactions
• A neutralization reaction occurs when an acid
and a base are reacted together.
• The two products are both NEUTRAL meaning
they are not acidic or basic.
acid + base  water + salt
both neutral
e.g. HCl(aq) + NaOH(aq)  H2O(l) + NaCl(aq)
Strong vs Weak
• A strong acid or base breaks into its ions more
easily than a weak acid or base does.
• For example:
Strong:
HCl  H+ + Cl(almost all of the HCl
molecules break up
into H+ and Cl- ions)
Weak:
HC2H3O2  H+ + C2H3O2(most of the HC2H3O2
DO NOT break into
ions so there are only
a small amount of H+
ions)
Concentrated vs Dilute
• Acids and bases are solutions, which means
they are dissolved in water.
• If there is very little water added, the acid or
base will be concentrated.
• If there is a lot of water added, the acid or
base will be dilute.
• For example, a concentrated acid will have
more H+ ions and therefore have a lower pH
than a dilute acid.