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Precipitation – a solid forms when mixing
solutions.
Acid-Base – An acid or base are
neutralized.
◦ Acid – Donates H+
◦ Base – Accepts H+
◦ Transfer of hydronium ion (H+ ) from the acid to
the base
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HNO3 + Ca(OH)2 Æ
H+
Ca+2
NO3OHCH3COOH + Al(OH)3 Æ
CH3COOAl+3
H+
OH-
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NH3
+
HClO4 Æ
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CH3CH2NH2
+ HClO3 Æ
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What makes a substance behave as an acid?
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When it reacts with water it donates the H+ to water:
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HNO3 +
H2O Æ
acid
base
Strong acids are 100% ionized.
CH3COOH + H2O Æ
Weak acids are only slightly ionized because the products
combine to form reactants. Equilibrium
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Hydrochloric Acid
HCl
Hydrobromic Acid
HBr
Hydroiodic Acid
HI
Sulfuric Acid
H2SO4
Nitric Acid
HNO3
Perchloric Acid
HClO4
Chloric Acid
HClO3
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pH is used to indicate the strength of an acid
or base.
pH is related to the amount of H+ or H3O+
available.
pH scale:
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0
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acid
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basic
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One of the largest group of reactions
known.
Recognized by the transfer of electrons
from an electron donor – oxidation to an
electron acceptor – reduction.
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Oxidation involves the loss of
electrons. Substance that gives
electrons away
Reduction involves the gain of
electrons. Substance that accepts
electrons.
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Oxidation Reduction Reactions
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Write the reaction for the formation of sodium
chloride from its elements:
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What is the charge of sodium in the reactant side?
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What is the charge of chlorine in the reactant side?
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Who is getting reduced?
- 1e- per Na
2Na(s) + Cl2(g) → 2NaCl(s)
+ 1e- per Cl
•Oxidizing agent gets reduced and helps the other
substance get oxidized.
•Reducing agent gets oxidized and helps the other
substance get reduced.
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Formation of ionic compounds from their
elements.
Decomposition of ionic compounds into
their elements.
Charge of elements in their standard state
is zero.
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Metal Displacement – A metal displaces a
metal cation from its place by giving its
electrons.
Hydrogen Displacement – A metal displaces
hydrogen from an acid solution by giving its
electrons.
Cu (s) + AgNO3 Æ
Metal Displacement Reaction
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Anytime that a substance is burned in the
presence of oxygen (reacts with O2).
CH4(g) + O2(g) → CO2(g) + H2O(g)
Who gets oxidized?
Who gets reduced?
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An atom is oxidized if it
◦ gains oxygen (is attached to more oxygen atoms in the
product than in the reactant) OR
◦ loses hydrogen (is attached to fewer hydrogen atoms in
the product than in the reactant)
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An atom is reduced if it
◦ loses oxygen (is attached to fewer oxygen atoms) OR
◦ gains hydrogen (is attached to more hydrogen atoms)
Important for organic compounds.
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Acid-Base
Redox
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◦
◦
◦
Combustion
Acid Displacement
Metal Displacement
Formation, Decomposition
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Addition of hydrogen gas (H2) in the presence
of platinum (Pt), catalyst, to unsaturated
hydrocarbons.
Alkenes
Alkynes
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Is oxidation or reduction occurring?
Important in Biological Reactions
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Draw and name the product formed when the
alkenes react with H2 and Pt.
a.
3-chloro-1-butene
b.
1,3-dimethylcyclopentene
How many molecules of H2 are needed for
1-butyne?
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Water is a reactant or product in a number of
reactions important to organic and
biochemistry.
In this section we will take a look at
three of them –
1. hydration
2. dehydration
3. hydrolysis
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Hydration
Water is added to a double bond but
needs acid (H+) as catalyst.
What functional group forms?
Alkene Æ alcohol
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Dehydration is the reverse of
hydration.
Water is removed to form a double
bond. Hydrogen in the adjacent
carbon has to be available.
Alcohol Æ Alkene
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Water (hydro) is used to split (lyse) a molecule.
Esters are one class of molecules that undergo
hydrolysis – when treated with water in the
presence of hydroxide ion (OH-) they split to form
a carboxylate ion and an alcohol.
Reaction used to make soap.
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Hydrolysis is one of the factors that determine
the length of time that some drugs remain
active.
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Ester Æ carboxylate + alcohol
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Alkenes can be hydrated.
` Alcohols
` Esters
can be dehydrated.
can be hydrolyzed.
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C
C
C
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3
4
C
C
C
OH
C
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C
6
C
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H+
heat
H2O
H+
H2O
OH-
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Draw the missing reactant for each
reaction.
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