Classifying Mixtures
A mixture is a physical
blend of two or more
substances.
Two Types:
• Heterogeneous
• Homogeneous
• Heterogeneous: not
uniform in composition
(ex. a salad)
• Homogeneous:
completely uniform in
composition (ex. salt
water)
• homogeneous mixtures
are called solutions
Solutions:
have the same
composition throughout
and can be gases,
liquids, or solids. Any
part of a system with
uniform composition and
properties is called a
phase
Types of Solutions
Liquid-Gas
Liquid-Liquid
Solid-Liquid
Solid-Solid
Gas-Gas
Gas-Liquid
Elements & Compounds
• Elements: smallest form of matter that can exist
under normal laboratory conditions, elements
cannot be separated into simpler substances~
Building Blocks
• Compounds: Two or more elements combine
with one another to form compounds.
Compounds are substances that can be
separated into simpler substances only by
chemical means. (Ex. if you burn sugar, it
eventually turns black, breaking down into
carbon and water vapor. Water can still be
broken down, so it is a compound. Carbon
cannot, so it is an element.)
Fermentation of Sugar
• Gay Lussac discovered the general chemical
equation for the breakdown of sugar into
ethanol and carbon dioxide:
• C6H12O6---- 2CH3CH2OH + 2CO2
Chemical Symbol
• Chemical Symbol: each element is
represented by a one or two letter
chemical symbol
• Examples: C, N, O, H, Na, Cl, F, Mg, S
Review
• Which of the following are Homogeneous?
Heterogeneous?
(a)Hetero
(a) spaghetti sauce
(b)Homo
(b) glass
(c)Hetero
(c) muddy water
(d)Homo
(d) cough syrup
(e)Homo
(e) mixture of nitrogen gas and helium gas
Review
Name the type of
solution
(a) Sodium Chloride in
water (brine)
(b) Copper in Silver
(sterling silver alloy)
(c) Water vapor in air
(moist air)
(d) Acetic acid in water
(vinegar)
Types of
Solutions
Liquid-Gas
Liquid-Liquid
Solid-Liquid
Solid-Solid
Answers
a. Solid-Liquid
b. Solid-Solid
c. Liquid-Gas
d. Liquid-Liquid
Review
• What would be an
example of a GasGas solution?
• Carbon dioxide and
oxygen in nitrogen
(air)
• What would be an
example of a GasLiquid solution?
• Carbon dioxide in
water
Review
• Classify each of the
following as a
substance or a mixture
(a) silver
(b) alphabet soup
(c) textbook
(d) table salt (NaCl)
(a) substance
(b) mixture
(c) mixture
(d) substance
Review
How do you distinguish between an element and a
compound?
• Compounds can be separated by physical means
into elements; elements cannot be separated into
simpler substances by chemical techniques
• Compounds can be separated by chemical means
into elements; elements cannot be separated into
simpler substances by chemical techniques
• Compounds can be separated by physical means
into elements; elements can be separated into
simpler substances by chemical techniques
• Compounds can be separated by chemical means
into elements; elements can be separated into
simpler substances by chemical techniques
Review
• What is the chemical
symbol for each of the
following elements?
• Silver
• Copper
S
C
Cu
Co
Cd
• Phosphorus
Pb
Sn
P
Po
Se
Sn
Ag
• Sodium
Sn
Sb
Na
S
Review
• Name the chemical
elements represented
by the following
symbols
• Sn
Lead
Tin
Sulfur
• Ca
Cadmium
Calcium
Chlorine
• S
Sulfur
Tin
Selenium