Name ___KEY____________________________________ Date __________________ Period _________
Pure Substances and Mixtures
Predictions:
1. What is your definition of the word PURE, as it relates to a “pure substance?”
2. What is your definition of the word MIXTURE?
3. If you, a scientist were given an unknown sample of matter, how could you tell whether it was a pure
substance or mixture? (What would you look for? What tests would you do?)
Appearance: crystals, shape, microscope, colors
Heat: melting point, boiling point
Test: add water—dissolve, separate; sink/float – density; add acid; chemical tests
Concept Map Notes:
Pure Substances, Mixtures and Solutions – Practice!
1. Look at the substances listed below. For each substance determine whether it is a pure substance, a
heterogeneous mixture or a homogeneous solution.
a.
Salad – Mixture, heterogeneous
b. Sugar – Pure substance, compound
c. Club soda – Mixture, homogeneous (solution)
d. Chex Mix – Mixture, heterogeneous
e. Mercury – Pure substance, element
f. Brass – Mixture, homogeneous (solution) alloy
g. Salt water – Mixture, homogeneous (solution)
h. Graphite – Pure substance, element
i. Salad dressing – Mixture, heterogeneous
j. Nitrogen – Pure substance, element
Content Dictionary:
Term
Definition
New Examples (not given in class)
Pure
Substance
Contains only one type of atom
or one type of molecule
Element (carbon, neon,
etc), compound (sugar,
water)
Mixture
A combination of two or more
substances that have NOT
combined chemically (can be
separated by physical means)
Granite, salt water
Compound
Each molecule consists of a
ratio of elements that are always
the same (a compound can be
separated only by chemical
means)
Sugar, water, Carbon
dioxide
Homogeneous
Looks like same substance
throughout
Heterogeneous Looks like multiple substances
Solution: Salt water,
Soda
Mixture: Oil and
vinegar