Practice
Exam
1
(Chapters
1, 2, and 3)
1.
Which
of the
following
is a
homogenous mixture
(^
air b.
sand
c.
pure water
d.
wood
2.
A
student carried
out
four
sets
of
independent measurements
in the
laboratory
for
determining
the
density
of a
liquid
at 25 ° C . The
best known accurate value
for the
density
of the
liquid
is
1.253
g/mL.
The
four
sets
of
measurements
can be
classified
according
to
their degree
of
precision
and
accuracy
as
Measurement
1
Measurement
2
Measurement
3
Measurement
4
1.000
^3-
(1.200
«0/1.252
t^.
C
0.253
0.925
|.xt|fl.201
i.is'il
L253
J-2-S3/1-253
2.001
V.202
(..I-254
'
*-2.253
a.
Good precision
and
good accuracy (set
#1)
<po*»f
y3^eC\5rov>
^
pt>o*~
T)^
Good precision
and
good accuracy
(set
#3) food
•*•»
&
ftovd
c.
Poor precision
and
poor
accuracy
(set
#2)
<§0&d
,x
3
d.
Good precision
and
poor
accuracy
(set
#4)
p01>
y
*s
£
3.
Consider
the
following diagram
for
classifying
the
process
as
B
CD
A
physical
process
A
meaningless process
An
unbalanced chemical reaction
A
balanced chemical reaction
Use
the
above diagram
to
provide
the
correct answer
A,
B, and C are
polyatomic molecules
B
are
diatomic molecules
B,
C, and D are
diatomic molecules
B,
C, and D are
polyatomic molecules
Two
blocks
of
copper
and
aluminum,
the
mass
of the
aluminum block
is
50.0
g.
What mass
of
copper
has the
same volume
of the
aluminum block? Densities
of
copper
and
aluminum
are
8.96
g.cm"3
and
2.70
g.cm"3,
respectively. Give your
answer with
the
proper number
of
significant figures.
g)l66g
b.
165.926
g c.
1.66g
d.
172
g
What volume
of
copper
has the
same
mass
as
100.0
cm3
of
aluminum?
The
densities
of
aluminum
and
copper
are
2.70
g.cm"3
and
8.96
g.cm"3,
respectively
a.
13.7cm3
(bA30.1
cm3
c.
15.0cm3
d.
27.4
cm3
