Classifying Chemical Compounds Organic compounds are

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8.1
Classifying Inorganic Compounds
• Compounds that have a high percentage of carbon
by mass are classified as organic compounds;
otherwise they are considered to be inorganic
compounds.
VOCABULARY
organic compounds
inorganic compounds
acids
bases
• Inorganic compounds can be molecular or ionic
based on the type of bonds that hold the components
(elements) together.
salts
• Inorganic ionic compounds
can be classified as acids,
bases, or salts depending
on their properties.
pH scale
aqueous
acidity
8.1
Classifying Inorganic Compounds
• Salts are substances that release positive ions and
negative ions other than H+ and OH- in solution.
• For example sodium chloride, NaCl
• Acids are substances that release H+ ions in solution;
bases are substances that release OH- ions in solution.
• Acidity is the measure of the relative amounts of H+
and OH- in a solution and is often measured on a
pH scale.
VOCABULARY
organic compounds
inorganic compounds
acids
bases
salts
aqueous
acidity
pH scale
8.2
Another Look at Bonding—
Lewis Diagrams
VOCABULARY
• Lewis diagrams only show valence
electrons, which are typically
represented by dots around the
element’s symbol.
Lewis diagram
bonding pair
electron dot diagram
octet rule
covalent chemical bond
• Wherever possible, an element's
valence electrons are arranged as
single electrons before bonding occurs.
lone electron pairs
• Single electrons from one element pair
with single electrons from other elements
to form bonding pairs of electrons.
• Atoms of elements tend to complete their
valence shells similar to the nearest noble
gas. This is known as the octet rule.
noble gas
8.3
Organic Compounds
• Organic chemistry is the chemistry of carbon
compounds.
• Organic molecules contain carbon, hydrogen, and
sometimes oxygen, nitrogen, and other non-metals,
and they have covalent bonds.
• Simplified Lewis diagrams or structural formulas can
be drawn to help visualize organic molecules.
VOCABULARY
organic chemistry
structural formulas
hydrocarbons
8.3
Organic Compounds
• Organic compounds are so numerous that an
elaborate classification system is necessary.
• Families of organic compounds include hydrocarbons,
alcohols, and ethers.
hydrocarbon
alcohol
ether
VOCABULARY
organic chemistry
structural formulas
hydrocarbons
CHAPTER
8
Classifying Chemical Compounds
• All chemical compounds are either organic
or inorganic.
• Compounds that have a high percentage
of carbon by mass are classified as
organic compounds; otherwise they are
considered to be inorganic compounds.
• Inorganic compounds can be molecular or ionic.
• They can also be classified as acids, bases, or salts depending on
their properties.
CHAPTER
8
Classifying Chemical Compounds
• Lewis diagrams (electron dot) illustrate how molecular compounds
form as a result of bonding pairs of electrons.
• Lewis diagrams only show valence electrons.
• Atoms of elements have a tendency to achieve complete valence
shells similar to their nearest noble gas. This is the octet rule.
CHAPTER
8
Classifying Chemical Compounds
• Organic compounds are molecular and contain carbon and hydrogen.
• They may also contain oxygen, nitrogen, and other non-metals.
• Families of organic compounds include hydrocarbons, alcohols, and
ethers.
CHAPTER
8
Classifying Chemical Compounds
Activity
Using the information in Tables 1 and 2 on page 203, classify each
compound below as an acid, base, or salt based on its properties:
1. HCl: reacts with metals; turns litmus paper red
2. KBr: conducts electric current; chemical indicators do not change colour
3. NH3: turns methyl red indicator yellow
4. NaNO3: does not react with metals; conducts electric current;
phenolphthalein indicator remains colourless
5. HNO3: turns indigo carmine from yellow to blue
CHAPTER
8
Classifying Chemical Compounds
Key Ideas
• All chemical compounds are either organic or inorganic.
• Inorganic compounds can be molecular or ionic (acids, bases,
or salts).
• Lewis diagrams (electron dot) can explain how molecular
compounds form as a result of bonding pairs of electrons.
• Organic compounds are molecular and contain carbon and
hydrogen.
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