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Science TAKS:
Bell Ringers
Prepared for the Scurry-Rosser High School
Science Department
Objective 4, I.07A
Investigate and identify properties of fluids
including density, viscosity, and buoyancy.
Important Definitions
• Buoyancy - The force that causes objects to float. According to the
principle of Archimedes, when a solid is placed in a fluid (a liquid or a
gas), it is subject to an upward force equal in magnitude to the weight
of the fluid it has displaced.
• Density - A measure of the quantity of some physical property
(usually mass) per unit length, area, or volume (usually volume).
– Mass density is a measure of the mass of a substance per unit volume.
Most substances (especially gases such as air) increase in density as
their pressure is increases or as their temperature decreases.
– Energy density is a measure of the amount of energy (often in the form
of electromagnetic radiation) per unit volume in a region of space or
some material.
– Population density is the number of individuals, such as inhabitants or
housing units, per unit of area.
• Viscosity - The resistance of a substance to flow.
– For example, water has a lower viscosity than molasses and flows more
easily.
#1) A block of maple wood with a volume of
405 cubic centimeters and a density of .67 g/cm3 is sawed in half. The density of
the two smaller blocks is now
A. one-fourth the original density
B. one-half the original density
C. two times the original density
D. the same as the original density
State Average: 31% correct
#2) This pipette is filled with a 20% NaOH
solution. The solution is at 20oC and has a
density of 1.23 g/mL. According to this
information, what is the mass of this
NaOH solution?
F. 3.88 g
G. 15.7 g
H. 23.9 g
J. 24.6 g
State Average: 53% correct
#3) Swimmers find that they can float more
easily in the ocean than in a freshwater
pond. The most likely reason for this
phenomenon is that the
A. viscosity of pond water is greater than that of
ocean water.
B. density of ocean water is higher than that of
pond water.
C. temperature of pond water is lower than that of
ocean water.
D. mass of ocean water is greater than that of pond
water.
State Average: 53% correct
#4) A sample of an element has a volume of
78.0 mL and a density of 1.85 g/mL. What
is the mass in grams of the sample?
Record and bubble in your answer to the
nearest tenth on the answer document.
___ ___ ___ . ___ ___ ___
State Average: 56% correct
Use the information below and your knowledge of
science to answer questions #42-44
• Soap-Making Project Materials:
• 125 mL cooking oil
• Safety goggles
• Stirring rod
• 100 mL H2O
• Apron
• 10 g NaOH
• 500 mL beaker
Procedure:
• Measure and add 100 mL of H2O to 125 mL of cooking oil and mix
thoroughly.
• Carefully and slowly add 10 g of NaOH while stirring constantly.
• Stir until a thick paste forms.
• Pour the paste into a mold and let it sit for two days.
• Remove the solid bar from the mold.
Caution:
Keep this soap away from the face and eyes because traces of NaOH
may still be present on the soap bar. Use this soap for washing floors and
tools only.
#5) A bar of soap produced by this soapmaking process normally sinks to the
bottom of a container of water. Which of
these processes could cause the bar of
soap to float in water?
A. Making grooves in the surface of the thick paste.
B. Adding air bubbles to the thick paste.
C. Letting the thick paste sit for four days.
D. Chilling the mold filled with the thick paste.
State Average: Tested Oct-2005
TAKS Question Set Answers
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#1
#2
#3
#4
#5
D
C
B
144.3 g
B