Acids

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Acids
Properties of Acids
1. Taste sour (but only taste if Mr. Conrad
says its O.K.)
2. Reacts with metals to form Hydrogen. This is
corrosive- eats away other materials.
3. Reacts with Carbonate to form Carbon Dioxide.
4. Turns blue litmus red. This is an indicator-a
compound that changes color when in contact with
Acids or Bases.
5. Dissociates (breaks apart) in water to form H
6. Has a pH range of 0-7.
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Properties of Bases
1. Taste bitter (but only taste if I say its
O.K.)
2. Feel slippery if touched (But BE CAREFUL!)
3. Turns red litmus paper blue.
4. Dissociates in water to form OH-
5. Used as cleaning products
6. Do not react with metals or carbonate
7. A pH range of 7-14.
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pH scale
A scale that expresses the concentration of H
ions in a solution. Its values range from 0-14.
Acids range from 0-7
Bases range from 7-14
Exactly 7 is neutral-gt its not an acid or a
base.
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Acids and Bases in Solution
Acids in a water solution dissociate (separate)
into H and a - ion (whatever is left)
HSO4 ---gt
H and SO4-
H and Cl-
HCl ---gt
Bases in a water solution dissociate (separate)
into OH- and a ion (whatever is left)
NH3 and OH-
NaOH ---gt
Na and OH-
NH3OH ---gt
Refers to how well an acid or base produce ions
(H and OH-) in water.
Strength
A strong acid/base will dissociate almost
completely. A weak acid/base will dissociate very
little. This determines how safe and acid/base is
to use
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When an acid reacts with a base. It always
produces a salt and water.
Neutralization reactions
HCl NaOH ---gt NaCl HOH
H2SO4 LiOH ---gt HOH Li2SO4
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Polymers, metals and alloys
What do cells in your body have in common with
plastics?
Both contain organic compounds- atoms of carbon
bonded to each other and additional atoms.
Carbon is present is more than 2 million
compounds with more being discovered every year.
Carbon is unique because of its ability to form
4 covalent bonds.
Carbon can form a variety of compounds, and a
variety of shapes including
Straight lines, branched chains, and rings
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Chains
C C C C C C
Branched Chains
Carbon Compound Shapes
C C C C C C C C C
Rings
C C C C C C
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polymer
A large complex molecule built from smaller
molecules joined together.
These form when large numbers of monomers bond in
a repeating pattern.
monomers
Smaller molecules that make-up polymers
There are two main types of polymers
Natural and Synthetic
Natural polymers can be grouped into 2 groups
Plant
Animal
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Plants contain long fibers that are bundled
together. These are called cellulose. Cellulose
is made of sugar molecules. Look very closely at
a paper towel, you can actually see pieces of
cellulose.
Animal polymers include
Spider webs- one of the strongest materials known!
Silk- fibers in silkworm cocoons!
Wool
fingernails
muscles
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PLASTICS - SYNTHETIC (MAN-MADE) POLYMERS THAT CAN
BE MOLDED OR SHAPED INTO USEFUL ITEMS.