1. Section 3.3 Mixtures of Matter
Contrast mixtures and substances.
Classify mixtures as homogeneous or heterogeneous.
List and describe several techniques used to separate mixtures.
substance: a form of matter that has a uniform and unchanging composition; also known as a pure substance
Section 3-3

2. Section 3.3 Mixtures of Matter (cont.)
heterogeneous mixture
homogeneous mixture
solution
filtration
distillation
crystallization
sublimation
chromatography
Most everyday matter occurs as mixtures—combinations of two or more substances.
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3. Homogeneous mixtures are also called solutions. Examples…
A mixture is a physical combination of two or more pure substances in which each pure substance retains its individual chemical properties.
A homogenous mixture is a mixture where the composition is constant throughout.
Homogeneous mixtures are also called solutions.
Examples…
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4. Solution homogeneous very small particles no Tyndall effect
particles don’t settle
EX: rubbing alcohol
Tyndall Effect: The scattering of light by particles.
C. Mixtures

5. Mixtures (cont.)
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6. mixture is not uniform in composition Examples…
Mixtures (cont.)
A heterogeneous mixture is a mixture where the individual substances remain distinct.
mixture is not uniform in composition
Examples…
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7. Colloid heterogeneous medium-sized particles Tyndall effect
particles don’t settle
EX: milk
C. Mixtures

8. Suspension heterogeneous large particles Tyndall effect
particles settle
EX: fresh-squeezed lemonade
C. Mixtures

9. Examples: colloid mayonnaise suspension muddy water fog solution
saltwater
Italian salad dressing
C. Mixtures

10. Separating Mixtures
Filtration is a technique that uses a porous barrier to separate a solid from a liquid in a heterogeneous mixture.
Distillation is a separation technique for homogeneous mixtures that is based on the differences in boiling points of substances.
Crystallization is a separation technique for homogenous mixtures that results in the formation of pure solid particles from a solution containing the dissolved substance.
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11. Separating Mixtures (cont.)
Sublimation is the process of a solid changing directly to a gas, which can be used to separate mixtures of solids when one sublimates and the other does not.
Chromatography is a technique that separates the components of a mixture on the basis of tendency of each to travel across the surface of another material.
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12. A B C D Section 3.3 Assessment
Which is NOT a technique for separating a homogenous mixture?
A. crystallization
B. distillation
C. filtration
D. chromatography A B C D
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13. A B C D Section 3.3 Assessment
Which of the following is a heterogeneous mixture?
A. seawater
B. silver mercury amalgam
C. atmosphere
D. salad dressing A B C D
Section 3-3