Worksheet 2.2, 2.3 - More Elements
Compounds and Mixtures
Homogeneous
matter has the same composition and
properties throughout a sample. All
compounds and elements are homogeneous.
Mixtures that are homogeneous are called solutions. Mixtures can
also be heterogeneous when they consist of visibly different substances
or phases and do not have the same composition and properties throughout a
sample.
An
alloy is a homogeneous mixture or
solution containing two or more metallic elements or metallic and nonmetallic
elements usually fused together or dissolving into each other when molten.
Classify
each of the following as homogeneous or heterogeneous and then as an element, compound or
mixture. In each case, explain
your classifications. Links have been provided
if you need more information.
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kind of matter |
homogeneous or heterogeneous? |
element, compound or mixture? |
explain your classification |
1 |
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2 |
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3 |
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4 |
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5 |
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6 |
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7 |
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8 |
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9 |
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10 |
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11 |
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12 |
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13 |
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14 |
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15 |
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Questions:
1. You are given two clear liquids – one is a compound
and one is a mixture. Describe
laboratory methods by which you could determine which is which.
2. You are given two white powders, sample A and
sample B. When heated, sample A turns
into a black solid and a clear liquid.
Sample B does nothing. Is sample
A an element, compound or mixture or can’t you tell conclusively? What about sample B? Explain.
3. Classify each of the following properties as
belonging to elements (E), compounds (C), or mixtures (M). List
all possible answers.
a. pure
substance _____
b. smallest
unit retaining its properties is an atom _____
c. components
can be separated by physical means _____
e. components
cannot be separated by physical means ____
f. always
the same properties throughout _____
g. components
can only be separated by nuclear changes
_____
h. components
can be present in varying proportions _____
i. components
are present in definite proportions _____
k. always
homogenous _____
j. components
do not retain their original properties _____
l. smallest
unit retaining its properties is a molecule _____
m. homogeneous
only if it is a solution _____
n. contains
only one kind of atom _____