Grade 9 Practice exam
Multiple Choice: Complete 60 of 71
Identify the letter of the choice that best completes the statement or answers the question.
____
____
____
____
____
____
____
____
____
____
1. The density of glycerol is 1.26 g/cm3. What would be the mass of 250 cm3 of glycerol?
a. 315 g
c. 248.7 g
b. 198.4 g
d. 251.3 g
3
2. The density of ice is 0.92 g/cm and the density of rubbing alcohol is 0.80 g/cm3. If an ice cube is placed in a
container of rubbing alcohol, the ice cube will
a. float in the rubbing alcohol with none of the ice cube submerged.
b. sink to the bottom of the container.
c. move up and down in the rubbing alcohol.
d. float in the alcohol so that most of the ice cube is below the surface of the liquid.
3. Identify the chemical change in the following:
a. the crushing of stones
c. the separation of cream from milk
b. the formation of clouds
d. the burning of a candle
4. Which one of the following is an example of a chemical change?
a. the melting of candle wax
c. the rotting of food
b. making sawdust by sawing wood
d. the breaking of glass
5. All of the following statements are part of the particle theory of matter except one. Identify the exception.
a. Different substances are made of different particles.
b. The particles in solids are harder than the particles in liquids.
c. The particles are always moving.
d. There are forces of attraction between the particles.
6. Which one of the following statements about the particles in a piece of silver is incorrect?
a. All of the particles have the same mass.
b. The particles are always moving.
c. There are strong forces of attraction between the particles.
d. As the temperature increases, the particles move more slowly.
7. Scientists have been able to identify about 110 elements and a few million compounds. How many different
kinds of atoms are there?
a. About 110.
b. A few million.
c. Two.
d. It's impossible to tell from the information given.
8. Which one of the following is a heterogeneous mixture?
a. Cooking oil
c. Salt water
b. Vinegar and water
d. Oil and water
9. Which of the following materials, based on appearance, is not a solution?
a. Perfume
c. Spaghetti sauce
b. Vinegar
d. Apple juice
10. Which of the following lists of properties is characteristic of metals?
a. Shiny, brittle, conduct heat and electricity.
b. Shiny, malleable, conduct heat and electricity.
c. Shiny, malleable, do not conduct heat and electricity.
d. Shiny, malleable, conduct heat but not electricity.
____ 11. The total number of atoms represented by the formula K2Cr2O7 is
a. 1.
c. 11.
b. 3.
d. 28.
____ 12. Carbon dioxide and carbon monoxide are compounds made up of the elements carbon and oxygen. Based on
that information only, which of the following statements is most likely correct?
a. The two compounds have different properties.
b. Carbon dioxide is a gas and carbon dioxide is a liquid.
c. The two compounds have the same properties.
d. One compound is more poisonous than the other.
____ 13. For hundreds of years up to about A.D.1600, a group of people called alchemists carried out thousands of
experiments and invented many pieces of laboratory equipment that we still use today. The major goal of the
alchemists was to
a. find evidence for the existence of atoms.
b. turn gold into iron or lead.
c. turn metals such as iron and lead into gold.
d. prove that fire, earth, air, and water were elements.
____ 14. The symbol Cl represents an atom with
a. 17 protons, 20 electrons, 20 neutrons.
c. 20 protons, 20 electrons, 17 neutrons.
b. 17 protons, 17 electrons, 17 neutrons.
d. 17 protons, 17 electrons, 20 neutrons.
____ 15. An atom with an atomic number of 38 and a mass number of 88 contains
a. 50 neutrons.
c. 38 neutrons.
b. 50 electrons.
d. 88 protons.
____ 16. The densities of some of the noble gases are shown below.
Ar 1.78 g/L
He 0.18 g/L
Kr 3.74 g/L
Ne 0.90 g/L
____ 17.
____ 18.
____ 20.
____ 23.
____ 24.
Use this information and what you know about periodic trends to give an estimate for the density of
xenon (Xe).
a. More than 5 g/L
c. Between 1 and 3 g/L
b. Between 0.1 and 1 g/L
d. Less than 0.18 g/L
Elements that possess some properties of metals and some properties of nonmetals are called
a. alkali metals.
c. noble gases.
b. metalloids.
d. heavy metals.
Cesium is a member of the alkali metal group. The formulas of cesium chloride and cesium oxide are
a. CsCl and CsO.
c. CsCl2 and CsO.
b. CsCl and Cs2O.
d. CsCl and CsO2.
All members of this group of elements form ions with a -1 charge when they react. What group is this?
a. Noble gases
c. Metalloids
b. Halogens
d. Alkali metals
Only one of the following statements is correct. Identify that statement.
a. All compounds are pure substances.
b. All mixtures are heterogeneous.
c. All pure substances are elements.
d. All solutions consist of a solid dissolved in a liquid.
Only one of the following statements is correct. Identify that statement.
a. All compounds consist of two or more elements.
b. All pure substances are elements.
c. All mixtures are solutions.
d. All solutions are heterogeneous.
____ 25. A pure substance consisting of two or more kinds of atom is considered to be
a. an element.
c. a compound.
b. a solution.
d. a heterogeneous mixture.
____ 26. Substances composed of identical atoms are
a. mixtures.
c. compounds.
b. elements.
d. solutions.
____ 27. A substance composed of two or more elements chemically combined is called
a. a mixture.
c. a solution.
b. a compound.
d. a precipitate.
____ 29. Only one of the following statements about molecules is correct. Which one?
a. All molecules consist of two atoms joined together.
b. All molecules consist of identical atoms joined together.
c. Molecules cannot be split apart.
d. All water molecules consist of two hydrogen atoms and one oxygen atom.
____ 30. Silicon dioxide, SiO2, is the major component of sand. Silicon dioxide is considered to be a compound
because
a. it is a pure substance.
c. it is a very common substance.
b. it consists of two different elements.
d. its composition varies.
____ 31. A heterogeneous mixture differs from a solution because
a. a heterogeneous mixture is always solid.
b. a heterogeneous mixture consists of elements.
c. the different components can be seen in a heterogeneous mixture.
d. a heterogeneous mixture consists of more substances than a solution.
____ 32. A compound of chlorine and potassium is sometimes used as a substitute for salt for people who have a
restricted salt diet. The name of this compound is
a. chlorine potassium.
c. potassium chloride.
b. potassium chlorine.
d. potassium chlorate.
____ 33. Dalton's atomic theory was one of the most important theories in chemistry. In this theory, atoms were
considered to be
a. tiny indivisible spheres.
c. made up of smaller particles.
b. the same for all elements.
d. positively charged.
____ 34. The atomic model has been modified many times over the years. This happened because
a. scientists have become smarter with time.
b. new evidence became available to scientists.
c. the actual nature of the atom has changed with time.
d. more elements were discovered.
____ 35. Which scientist first proposed the existence of the nucleus in atoms?
a. Rutherford
c. Thomson
b. Bohr
d. Dalton
____ 36. One model of the atom is sometimes referred to as the "raisin bun" model. In this model, the raisins
represent the
a. protons.
c. nucleus.
b. neutrons.
d. electrons.
____ 37. Protons are
a. positively charged particles found outside the nucleus in an atom.
b. negatively charged particles found outside the nucleus in an atom.
c. neutral particles found in the nucleus in an atom.
d. positively charged particles found in the nucleus in an atom.
____ 38. Electrons are
a. positively charged particles found outside the nucleus in an atom.
b. negatively charged particles found outside the nucleus in an atom.
c. neutral particles found in the nucleus in an atom.
d. negatively charged particles found in the nucleus in an atom.
____ 39. Neutrons are
a. negatively charged particles found outside the nucleus in an atom.
b. neutral particles found outside the nucleus in an atom.
c. neutral particles found in the nucleus in an atom.
d. positively charged particles found in the nucleus in an atom.
____ 40. All of the following terms are associated with the atom. Which one has the smallest mass?
a. electron
c. neutron
b. proton
d. nucleus
____ 41. The number of electrons in an atom is the same as
a. the number of neutrons in the atom.
b. the mass number of the atom.
c. the number of protons in the atom.
d. the difference between the mass number and atomic number.
____ 42. If the atomic number of an atom is represented by X and the mass number is represented by Y, the number of
neutrons in an atom of the element is
a. Y-X.
c. X+Y.
b. X-Y.
d. Y.
____ 44. In Bohr's planetary model of the atom, he suggested that
a. electrons could be found only in certain orbits or energy levels.
b. the closer an electron is to the nucleus, the higher its energy.
c. electrons always stay in the same energy level.
d. the orbit closest to the nucleus can hold eight electrons.
____ 45. Which of the following is the correct arrangement of electrons in a sulphur atom, atomic number 16?
a. 2, 8, 4, 2
c. 6, 8, 2
b. 2, 8, 6
d. 2, 6, 8
____ 46. The number of electrons in the outermost orbit of a phosphorus atom is
a. 2.
c. 5.
b. 8.
d. 15.
____ 47. An atom can form a positive ion by
a. losing electrons.
c. losing protons.
b. gaining electrons.
d. gaining protons.
____ 48. Only one of the following elements is correctly described. Which one?
a. Element 11 is an alkali metal in period 2.
b. Element 17 is a halogen in period 17.
c. Element 18 is a noble gas in period 3.
d. Element 20 is a precious metal in period 2.
____ 49. The noble gases are very unreactive because
a. they are very rare.
c. they have very low densities.
b. their outer orbits are filled.
d. they have low boiling points.
____ 50. Argon gas is used to fill ordinary lightbulbs. The property of argon that makes it useful for this purpose is that
argon
a. is a very good conductor of electricity.
____ 51.
____ 32.
____ 53.
____ 54.
b. is a very unreactive gas.
c. is a good conductor of heat.
d. reacts with the metal in the bulb to produce light.
Rows in the periodic table are also referred to as
a. periods.
c. groups.
b. families.
d. columns.
All members of this group of elements form ions with a +1 charge when they react. What group is this?
a. Noble gases
c. Metalloids
b. Halogens
d. Alkali metals
The electrons in an atom of element X are arranged 2, 8, 2. The ion that this element is most likely to form is
a. X2-.
c. X2+.
b. X6-.
d. X6+.
Gallium is the element immediately under aluminum in the periodic table in group 13. Based on this
information, how many electrons is a gallium atom likely to lose or gain to form a stable ion?
a. 13
c. 2
b. 3
d. 1
____ 55. Which of the following is a good conductor?
a. silk
c. salt water
b. sand
d. silver
____ 56. Electrons will not travel freely through which of the following?
a. copper
c. Wood
b. carbon
d. Silver
____ 57. When electrons are flowing through an electric circuit, the switch that controls the circuit must be
a. open.
c. off.
b. closed.
d. ready.
____ 58. Static electric discharges release large amounts of energy but static electricity differs from current electricity
because it
a. does not involve energy.
b. does not flow from negative to positive.
c. is not controlled.
d. is not able to cause injury to people.
____ 59. A dry cell provides the electrical energy in a circuit when
a. electrons flow from the positive terminal through the external circuit to the negative
electrode.
b. protons flow from the positive terminal through the external circuit to the negative
electrode.
c. electrons flow from the negative terminal through the external circuit to the positive
electrode.
d. protons flow from the negative terminal through the external circuit to the positive
terminal.
____ 60. The SI unit for measuring electric potential (potential difference) is the
a. ohm.
c. joule.
b. ampere.
d. volt.
____ 61. Battery A consists of three 1.5-V cells in series and battery B consists of three 1.5-V cells in parallel. Which
of the following statements is correct?
a. Both batteries produce 1.5 V.
b. Both batteries produce 4.5 V.
____ 62.
____ 63.
____ 64.
____ 65.
____ 66.
____ 67.
____ 68.
____ 69.
____ 70.
____ 71.
c. Battery A produces 1.5 V and battery B produces 4.5 V.
d. Battery A produces 4.5 V and battery B produces 1.5 V.
An ohm is a unit of
a. electric potential difference.
c. current.
b. resistance.
d. power.
Ohm’s Law, stated in mathematical terms, is
a. R = V  I
c. R = V / I
b. R = I / V
d. R = V2  I
Which one of the following is not equivalent to the others?
a. R = V / I
c. V = I  R
b. I = V / R
d. I = V  R
The SI unit for measuring power is the
a. ampere.
c. volt.
b. watt.
d. joule.
Choose the planet that is completely different from the other three.
a. Jupiter
c. Mars
b. Neptune
d. Saturn
Which of the following planets does not have an appreciable atmosphere?
a. Mercury
c. Jupiter
b. Venus
d. Saturn
What object is most likely the birthplace of stars?
a. black hole
c. Nebula
b. supernova
d. neutron star
From the list given, choose the planet that has rings around it.
a. Pluto
c. Mars
b. Mercury
d. Jupiter
The visible part of the Sun is called
a. the chromosphere.
c. the surface.
b. the corona.
d. the photosphere.
What are prominences?
a. dark spots on the solar surface
b. large sheets of glowing gases bursting from the chromosphere
c. the region where nuclear fusion takes place
d. the outer atmosphere of the Sun
Matching
Match the electrical symbol in with the appropriate name.
a.
f.
b.
g.
c.
h.
d.
i.
e.
____
____
____
____
1.
3.
5.
7.
single cell
3 cells in series
ammeter
ground
__
__
2.
4.
6.
switch
resistor
voltmeter
11. Match the following (12 marks)
___1. A reaction producing carbon dioxide
___ 2. Removes surface water from earth
___ 3. Converts ammonia to NO3 1___ 4. The portion of the water cycle that involves ice
___ 5. A form of organic carbon
___ 6. A necessary part of the nitrogen and carbon cycles
___ 7. The process by which energy is passed from one
Tropic level to another
___ 8. The earth’s outer crust
___ 9. Converts good nitrogen to bad
___ 10. An inorganic form of carbon
___ 11. A surface water
___ 12. Contains ozone
A. precipitation
B. nitrate
C. consumption
D, lithosphere
E. hydrologic cycle
F. nitrogen fixation
G. stratosphere
H. calcium carbonate
I. lakes
J. combustion
K. denitrification
L. evaporation
M. sublimation
N. respiration
O. photosynthesis
P. bacteria
Q. troposphere
R. oil
Short Answer
1. Complete the blanks in the following table.(6 marks)
atomic
mass
number of
number of
number of
number
number
protons
electrons
neutrons
9
19
?
?
?
?
?
20
?
21
?
56
?
26
?
35
?
?
?
45
2. a. What is an ion? (2 marks)
b. Explain how an atom becomes a positive ion. (2 marks)
c. Explain how an atom becomes a negative ion. Write your answer in complete sentences.(2
marks)
3. Draw Bohr diagrams for (3 marks)
a. fluorine ion, atomic number 9, symbol F
b. silicon, atomic number 14, symbol Si
c. potassium ion, atomic number 19, symbol K
,
4. Complete the table below (9 marks)
Description
1
O2
2
Zn3(PO4)2
3
SiO4
Element
Compound
Ionic or
covalent
Number
of atoms
5. Complete the following table (4 marks)
Name
Atomic
Proton #
Neutron #
Notation
30
Electron #
Atomic
Mass
Number
28
Sulfide ion
magnesium
10
7
14
N
20
3-
Part C :Calculations: [28 marks]
1 If a blender motor uses 10 000 J of energy but only turns 9 700 J of that into useful
energy, what is the efficiency percentage of the blender? (3 marks)
2. Calculate the density in g/ cm3 of a wooden block that measures 5.0 kg and has
the following dimensions; 200 cm by 100 cm by 300 cm. (4 marks)
3.
A family goes on vacation for 5 days and forgets to turn the air conditioner off. Calculate the
cost of operating an air conditioner if it draws a current of 8 amps from a 120 volt outlet.
(Assume the unit runs non-stop and the
Rate = 7.0 cent/KW h) (4 marks)
4. A) An electric kettle is connected to a 120-V outlet and has a resistance of 9.6 ohms.
What is the current required to operate the kettle? [2 marks]
B ) Calculate the power used by a microwave oven that uses 112 500 J of energy in 2.5
minutes. [3 marks]
5.. Solve for all missing variables in the circuit below. (6 marks)
6.A) Draw a circuit diagram for a kitchen circuit that contains the exhaust fan, the stove,
and a ceiling light that has three bulbs (if one of the bulbs burns out the light does not
work). The circuit is also controlled by a switch at the hallway and one at the back door. [4
marks]
B) What problem did you encounter with the diagram? [1 mark]
C) What type of power source runs this circuit? [1 mark]
Short Answer [ 26 marks}
4.Compare the prosperities, placement on the periodic table and the electron arrangement of the
alkaline earth metals and the noble gases. [8 marks]
5. Compare and contrast the concepts of biomass and biodiversity in foodwebs. [4 marks]
6. Answer 3 of the following [9 marks]
A) Explain the significance of the red shift.
B) Explain how the aurora borealis is created
C) What are the stages of life of a sun?
7. Given the accompanying
diagram
A) List the following (6 marks)
Type of
All examples from the
organism
above
Autotroph
Herbivore
Omnivore
Top Carnivore
Heterotroph
B) Explain two effects that might happen to the above ecosystem if the wild cat were to be hunted to
extinction. [4 marks]
C) There are four factors that determine population changes over time. If a drought occurred in this
region, identify how these four factors might change. [4 marks]
D) State three abiotic conditions you would expect in this ecosystem. [3 marks]
E) Define carrying capacity and explain how the carrying capacity for mice could be altered. [4
marks]
8. What are the two most common elements found on the Sun? What role do they play in the energyproduction mechanism of the Sun? Write your answer in paragraph form.
9. Explain why "static cling" does not develop when a clothes dryer is used to dry a load consisting only of
cotton towels. Write your answer in complete sentences. [3 marks]
10. Examine the following figures. Explain how the schematic diagram in Figure 2 differs from the circuit shown
[ 2 marks]
exam
Answer Section
MULTIPLE CHOICE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
ANS:
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B
D
A
A
C
B
B
A
D
B
C
C
A
B
REF:
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REF:
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
LOC:
LOC:
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LOC:
UBC2
UBC2
UBC2
UBC4
UBC4
UBC3
UBC4
UBC5
UBC5
UBC5
DSIC6
UBC12
UBC6
UBC6
15.
16.
17.
18.
19.
20.
21.
22.
23.
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
42.
43.
44.
45.
46.
47.
48.
49.
50.
51.
52.
53.
54.
55.
56.
57.
58.
59.
60.
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A
D
D
B
C
A
C
A
A
A
B
C
A
C
B
B
A
D
C
B
C
D
C
D
D
A
B
A
C
A
B
C
D
A
D
D
A
C
D
C
B
C
C
D
D
B
REF:
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UC
UC
UC
UC
UC
UC
UC
AS
AS
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
LOC:
LOC:
LOC:
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UBC6
UBC6
DSIC7
DSIC7
DSIC7
DSIC7
UBC7
DSIC6
DSIC6
UBC7
UBC7
UBC7
UBC7
UBC9
UBC10
UBC10
UBC8
UBC9
UBC9
UBC9
UBC1
UBC1
UBC1
UBC1
UBC1
UBC2, UBC3
UBC2, UBC3
UBC2, UBC3
UBC4
UBC3, UBC4
RST3
UBC3
UBC3
UBC3
UBC10
UBC10
UBC4, RST3
UBC8
UBC1
UBC1
UBC4
UBC3
UBC4
UBC6
UBC9
UBC6
18
61.
62.
63.
64.
65.
66.
67.
68.
69.
ANS:
ANS:
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ANS:
ANS:
ANS:
ANS:
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C
D
B
C
A
C
D
D
B
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
UC
UC
UC
UC
UC
UC
UC
UC
UC
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
UBC7
UBC7
UBC6
UBC3
UBC3
UBC7
UBC3
UBC6
UBC6
D
H
C
B
I
E
A
REF:
REF:
REF:
REF:
REF:
REF:
REF:
AS
AS
AS
AS
AS
AS
AS
LOC:
LOC:
LOC:
LOC:
LOC:
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DSIC7
DSIC7
DSIC7
DSIC7
DSIC7
DSIC7
DSIC7
MATCHING
70.
71.
72.
73.
74.
75.
76.
ANS:
ANS:
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SHORT ANSWER
77. ANS:
The missing numbers are shown in boldface.
atomic
mass
number of
number of
number of
number
number
protons
electrons
neutrons
9
19
9
9
10
20
41
20
20
21
26
56
26
26
30
35
80
35
35
45
REF: AS
LOC: DSIC10
78. ANS:
a. An ion is an atom that has a positive or negative charge, caused by the atom losing or gaining electrons.
b. An atom becomes a positive ion by losing electrons. The number of protons is now greater than the
number of electrons.
c. An atom becomes a negative ion by gaining electrons. The number of electrons is now greater than the
number of protons.
REF: UC
79. ANS:
LOC: DSIC7
REF: AS
LOC: UBC7
80. ANS:
a. Atoms of the alkali metals all have one electron in their highest orbit.
b. Atoms of the halogens all have seven electrons in their highest orbit.
REF: UC
LOC: UBC9
81. ANS:
a. Transmission electron microscope or scanning electron microscope. This would depend on whether the
researcher wished to view the internal or external structure of the particle.
b. Light microscope. Electron microscopes would require the use of dead specimens. To make observations
of living specimens, the light microscope would be the best tool.
c. Transmission electron microscope. This would allow for internal mitochondrial detail to be imaged and
studied.
REF: MC
LOC: DS2, DS5
82. ANS:
The light microscope uses visible light to illuminate an object. The light passes through the specimen and is
focused using a series of glass lenses into an image at the eyepiece. The detail visible depends on the
wavelength of light used. A transmission electron microscope uses a beam of electrons as the illumination.
These pass through the specimen and are focused onto a fluorescent screen using a series of electromagnetic
lenses.
REF: UC
LOC: DS5, RST1
83. ANS:
Needham rekindled the debate of spontaneous generation by making observations of broth left to stand in a
flask sealed with a cork. He concluded that boiled broth would be a source of new life if left unattended.
REF: UC, MC
LOC: RST1
84. ANS:
Spallanzani repeated Needham's work but boiled the flasks longer and created an airtight seal. Although
microorganisms did not form in the boiled sealed flasks, protagonists of the theory of spontaneous generation
used the airtight seal to dismiss Spallanzani's results, suggesting that he prevented the "active principle" from
entering the flask and permitting the creation of microscopic life. However, Spallanzani did prove that longer
boiling would destroy all of the organisms in the flask, a point that would be necessary for Pasteur's work.
REF: UC, MC
LOC: RST1
85. ANS:
Prophase: chromatid pairs condense and become visible. Nuclear membrane disappears
Metaphase: chromatid pairs align along the centre of the cell.
Anaphase: chromatid pairs separate and migrate to the poles of the cell.
Telophase: chromosomes begin to uncoil. Nuclear membrane reforms. Cytokinesis begins.
REF: UC
LOC: UBC2, DSIC8
86. ANS:
Genetic material must be duplicated to ensure that the new daughter cells have a complete set of
chromosomes, and hence genes.
REF: UC
LOC: UBC3
87. ANS:
The genetic code is the sequence of the nucleic acid bases in a stretch of DNA. This sequence may vary
among individuals and will definitely vary between species. It is the order of the bases that makes each of us
unique.
REF: MC
LOC: UBC3
88. ANS:
Stem cells have retained the ability to divide without contact inhibition. In addition, they are unspecialized,
therefore their entire DNA code is active. Stem cells also have no limit in force on the number of divisions
they can undergo. Specialized cells exhibit contact inhibition; their DNA is only partially active.
REF: UC
LOC: UBC4, UBC5, UBC10, RST3
89. ANS:
Pollination is the process of fertilization in plants. Pollen is the male gamete and ova the female gamete.
When pollen combines with ova, pollination is said to have occurred.
REF: UC
90. ANS:
a. male
b. female
c. female
d. male
LOC: UBC5, RST2
REF: UC
LOC: UBC5, RST2
91. ANS:
Flowers of plants that depend on animals for pollination are usually brilliantly coloured and produce a nectar
of some sort. The colour and nectar are enticements for animals to approach and interact with the flower.
Stamen and pistil are usually positioned such that the animal would have to come in contact with them before
it can feed on the nectar. In this way the plant is assured of pollination. Flowers of plants that depend on the
wind tend to have very little in the way of coloration.
REF: UC, MC
92. ANS:
1. testis
2. epididymis
3. vas deferens
4. epididymis
LOC: UBC5, RST2
5. seminiferous tubules
6. support cells nourish the sperm cell as it matures
7. maturing sperm
REF: UC
LOC: UBC7, DSIC5
93. ANS:
In males, the parent cell undergoes meiosis to create four haploid cells, each of which will be transformed into
a sperm cell. In females, the parent cell undergoes meiosis to produce only one egg cell and four bar bodies.
The egg cell that is produced contains almost all of the original cell's cytoplasm. Eggs are non-motile and do
not possess a flagellum. Sperm cells contain very little cytoplasm and are motile.
REF: MC
94. ANS:
1. oviduct
2. uterus
3. endometrium
4. cervix
5. ovary
6. vagina
LOC: UBC7, UBC8, DSIC5, RST2
REF: UC
LOC: UBC7, RST2
95. ANS:
Estrogen promotes the development of the endometrium in the uterus. As ovulation approaches, estrogen
levels increase in the blood. Progesterone stimulates the development of the endometrium and its
maintenance. In addition, progesterone inhibits further ovulation.
REF: MC
LOC: UBC7, UBC8, RST2, DSIC5
96. ANS:
Only one sperm cell is permitted to penetrate the egg. The remaining sperm cells are destroyed by changes in
the egg immediately after conception. For the successful sperm cell, only the head portion that carries the
nucleus is permitted into the egg. The remainder, carrying the father's mitochondria and other cytoplasmic
components, remains outside and is destroyed.
REF: UC
LOC: UBC9, RST2
97. ANS:
The function of the placenta is to allow the fetus to gain nutrients from the mother's blood and dispose of
wastes. It is the organ that will nourish the fetus as it develops. It will also produce a hormone that will
maintain the uterine wall until the fetus is fully developed. It will then initiate contractions of the uterus to
begin the birthing process.
REF: UC
LOC: UBC9, RST2
98. ANS:
Static cling does not build up because all of the items in the dryer are made of the same material. There is no
tendency of electrons to move from one cotton towel to another.
REF: UC
LOC: UBC1
99. ANS:
In order for the electrons to be repelled from the end of the static wick, they must be concentrated in a small
area. This only happens when the end of the wick comes to a point. If the end is blunt, the electrons will
remain in the wick.
REF: UC
LOC: UBC1
100. ANS:
A "current" in a river or stream refers to the flow of water from one place to another. "Current" in an electrical
circuit refers to the flow of electrons through the circuit.
REF: UC
LOC: UBC4
101. ANS:
Figure 1 shows a single dry cell. Figure 2 shows a battery made up of four cells.
REF: UC
102. ANS:
Data
V=?
I = 6.8 A
R = 16.2 ohms
LOC: UBC4
Formula:
V=IR
V = 6.8 A  16.2 ohms
= 110 V
The voltage drop across the air conditioner is 110 V.
REF: UC
103. ANS:
Data:
V = 120 V
I=?
R = 9.6 ohms
LOC: UBC8
Formula:
V=IR
120 V = I  9.6 ohms
120 V / 9.6 ohms = I
I = 12.5 A
The current flowing through the kettle is 12.5 A.
REF: UC
LOC: UBC8
104. ANS:
Data:
Formula:
E = 112 500 J
P = E/delta t
delta t = 2.5 minutes
P = 112 500 J/150 s
= 2.5 min  60 s/min = 750 W
= 150 s
The microwave oven uses 750 W of power.
REF: UC
105. ANS:
Data:
P=?
V = 120 V
I = 7.5 A
LOC: UBC12
Formula:
P=VI
= 120 V  7.5 A
= 900 W
The coffee maker uses 900 W of power.
REF: UC
LOC: UBC12
106. ANS:
Data:
P = 25 W
V = 120 V
I=?
Equation:
P=VI
25 W = 120 V  I
25 W/120 V = I
I = 0.21 A
A 25-W bulb draws 0.21 A of current in a 120-V circuit.
REF: UC
LOC: UBC12
107. ANS:
Mars, Earth, Neptune, Jupiter.
REF: UC
LOC: UBC3
108. ANS:
Hydrogen serves as the nuclear fuel and helium is the fusion product.
REF: UC
LOC: UBC6
OTHER
109. ANS:
REF: AS
LOC: DSIC7
Short Answer
21. State two things you can do when carrying out an experiment to help prevent damage to you or your clothing.
22. Write a sentence describing the major difference between the way the elements are arranged in the modern
periodic table and the way they were arranged in Mendeleev's periodic table.
23. Examine the formulas given below.
KF, KOH, H2O, CS2, AlF3, K3PO4, CaCl2
Use these formulas and your knowledge of the periodic table to correct the following incorrect formulas.
a. SiO3
b. Al(OH)4
c. Ca2(PO4)3
d. Tl(PO4)2
24. In Mendeleev's periodic table, tellurium (Te) was listed before iodine (I), even though the atomic mass of
tellurium (127.6) is greater than that of iodine (126.9). Explain why it made sense for Mendeleev to do this,
when he arranged all of the other elements in order of increasing atomic mass.
exam
Answer Section
MULTIPLE CHOICE
1.
2.
3.
4.
5.
6.
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
17.
18.
19.
20.
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
ANS:
C
A
B
D
C
B
D
A
D
C
B
C
A
C
D
A
A
B
B
A
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
REF:
AS
AS
AS
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
UC
AS
AS
AS
UC
MC
UC
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
LOC:
DSIC1
UBC13
UBC13
UBC14
UBC14
UBC2
UBC2
UBC5
DSIC6
UBC2
UBC2
UBC12
UBC5
UBC6
DSIC6
DSIC6
UBC11
UBC8
UBC11
UBC9
SHORT ANSWER
21. ANS:
We could wear safety goggles or aprons. We should avoid sudden movements, and keep glass containers in
the middle of the desk, away from the edge. Any two of these would be acceptable.
REF: UC
LOC: DSIC1
22. ANS:
In Mendeleev's periodic table, the elements were arranged in order of increasing atomic mass. In the modern
periodic table, the elements are arranged in order of increasing atomic number.
REF: UC
23. ANS:
a. SiO2
b. Al(OH)3
c. Ca3(PO4)2
d. Tl(PO4)3
LOC: UBC8
REF: AS
24. ANS:
LOC: UBC11
The properties of iodine are similar to the properties of fluorine, chlorine, and bromine, so iodine should be
placed in the same column as those elements. The properties of tellurium more closely match the properties of
the elements in the column where Mendeleev placed it; they did not match the properties of fluorine, chlorine,
and bromine.
REF: UC
LOC: UBC8