Question 1
What is the definition of a scientific theory?
ANSWER
a model that explains the underlying reasons for observations and laws
Question 2
What term best describes a brief statement that summarizes many past observations and
predicts new ones?
ANSWER
scientific law
Question 3
Which of the following is an example of a scientific law?
ANSWER
In a chemical reaction, matter is neither created nor destroyed.
Question 4
Which of the following would be considered a theory?
ANSWER
Helium balloons float because helium is less dense than air.
1
,Question 5
The key to success in chemistry is:
ANSWER
all of the above
Question 6
A plastic block has dimensions of 2.2 cm x 3.0 cm x 1.5 cm and a mass of 12.4 grams. Will
the block float in water and why?
ANSWER
No, because the density of the block is 1.3 g/mL which is greater than the density of water.
Question 7
Given the density of Au is 19.3 g/cm3, determine the mass of gold (in grams) in an ingot with
the dimensions of 10.0 in x 4.00 in x 3.00 in.
ANSWER
3.80 x 104
Question 8
The distance between the two hydrogen atoms in a molecule of water is 0.000000000172 m.
Express this distance in scientific notation.
ANSWER
1.72 x 10-10 m
2
,Question 9
How many grams are in 1.48 x 107 μg?
ANSWER
14.8
Question 10
The correct decimal representation of 6.453 x 103 is:
ANSWER
6,453
Question 11
How many significant digits should be reported in the answer to the following question?
(4.3-3.7) x 12.3=
ANSWER
1
Question 12
The correct scientific notation for the number 0.00050210 is:
ANSWER
5.0210 x 10-4
Question 13
3
, Which measurement below represents the heaviest mass?
ANSWER
1 Mg
Question 14
Determine the answer to the following equation with correct number of significant figures:
2.02+8.102-0.0297=
ANSWER
10.09
Question 15
A lead ball has a mass of 55.0 grams and a density of 11.4 g/cm3. What is the volume of the
ball?
ANSWER
4.82 mL
Question 16
When the value 4.449 is rounded to two significant figures, the number should be reported
as:
ANSWER
4.4
Question 17
4
What is the definition of a scientific theory?
ANSWER
a model that explains the underlying reasons for observations and laws
Question 2
What term best describes a brief statement that summarizes many past observations and
predicts new ones?
ANSWER
scientific law
Question 3
Which of the following is an example of a scientific law?
ANSWER
In a chemical reaction, matter is neither created nor destroyed.
Question 4
Which of the following would be considered a theory?
ANSWER
Helium balloons float because helium is less dense than air.
1
,Question 5
The key to success in chemistry is:
ANSWER
all of the above
Question 6
A plastic block has dimensions of 2.2 cm x 3.0 cm x 1.5 cm and a mass of 12.4 grams. Will
the block float in water and why?
ANSWER
No, because the density of the block is 1.3 g/mL which is greater than the density of water.
Question 7
Given the density of Au is 19.3 g/cm3, determine the mass of gold (in grams) in an ingot with
the dimensions of 10.0 in x 4.00 in x 3.00 in.
ANSWER
3.80 x 104
Question 8
The distance between the two hydrogen atoms in a molecule of water is 0.000000000172 m.
Express this distance in scientific notation.
ANSWER
1.72 x 10-10 m
2
,Question 9
How many grams are in 1.48 x 107 μg?
ANSWER
14.8
Question 10
The correct decimal representation of 6.453 x 103 is:
ANSWER
6,453
Question 11
How many significant digits should be reported in the answer to the following question?
(4.3-3.7) x 12.3=
ANSWER
1
Question 12
The correct scientific notation for the number 0.00050210 is:
ANSWER
5.0210 x 10-4
Question 13
3
, Which measurement below represents the heaviest mass?
ANSWER
1 Mg
Question 14
Determine the answer to the following equation with correct number of significant figures:
2.02+8.102-0.0297=
ANSWER
10.09
Question 15
A lead ball has a mass of 55.0 grams and a density of 11.4 g/cm3. What is the volume of the
ball?
ANSWER
4.82 mL
Question 16
When the value 4.449 is rounded to two significant figures, the number should be reported
as:
ANSWER
4.4
Question 17
4
