Download June Exam Review Material World

Science & Techno 10
June Exam Review Material World
Review Problems for Science & Technology June Exam
MATERIAL WORLD UNIT
 Chapter on Atoms and Elements
1. Which of the following is true about Sodium?
a) It is an Alkali Metal
b) It is an Alkaline Earth Metal
c) It is a Halogen
d) It is a Noble Gas
2. Which of the following is FALSE about the Rutherford-Bohr diagram of
Phosphorus?
a) It has 15 protons
b) It has 15 neutrons(most isotopes will have 31-16 = 15 neutrons)
c) It has 15 electrons
d) It has 5 valence electrons
3. Which of the following is TRUE about fluorine’s Rutherford-Bohr diagram?
a) It has 1 energy level
b) It has 7 valence electrons
c) It has 17 electrons
d) It has 19 electrons
4. Which of the following Rutherford-Bohr diagrams is correct for Argon? D (for the ST exam,
know that a neutron is neutral, but they will only ask you to place protons in the nucleus, not
neutrons. See check list if you don’t believe me.)
a)
b)
+
18 p+
21 n0
18 p
40 n0
20 e– 20 e–
c)
2 e– 9 e– 10 e–
d)
18 p+
22 n0
18 p+
40 n0
2 e– 8 e– 8 e–
2 e– 8 e– 8 e–
Science & Techno 10
June Exam Review Material World
5. Which of the following is the correct Lewis diagram for Carbon? B (you have to
pair electrons; remember to use last shell electrons only)
a)
b)
C
c)
C
C
d)
C
6. Which of the following is the correct Lewis diagram for Mg? A
a)
b)
Mg
c)
Mg
d)
Mg
Mg
7. Which of the following is the Alkali metal in the 3rd period?
a) Sodium
c) Magnesium
b) Sulphur
d) Calcium
8. Which of the following is the Halogen in the 2nd period?
Science & Techno 10
June Exam Review Material World
a) Fluorine
b) Chlorine
c) Neon
d) Argon
9. Which of the following is true about the periodic table?
a) The period indicates the number of neutrons that an atom has
b) The Group number indicates the number of electrons that an atom has
c) The period indicates the number of protons that an atom has
d) The Group number indicates the number of valence electrons that an atom
has
10. Which of the following is ALWAYS true about the periodic table?
a) The number of protons is equal to the number of electrons (if the atom is
neutral; otherwise e= p –c, where c = charge)
b) The number of protons is equal to the number of neutrons
c) The number of electrons is equal to the number of neutrons
d) The number of valence electrons is equal to the number of protons
11. Where in the periodic table can you find the following:
a) an alkaline earth metal?
2nd column
b) a noble gas?
Last column
c) a halogen?
2nd last column
d) a metal?
To the left of staircase; exception H and most of
the ones touching(metalloids)
e) an atom containing only one
electron shell?
Ist row(H and He only)
Science & Techno 10
June Exam Review Material World
12. Two elements X and Y have the following properties.
Element X
Element Y
Without metallic luster
Metallic luster
Four valence electrons
Two valence electrons
th
6 protons
Located in the 4 period
Which symbols from the periodic table correspond to elements X and Y respectively?
A) Ca and C
B) K and B
C) K and C
D) Ca and B
13. Which of the following statements about the properties of metals is correct?
A) They are malleable but are not shiny.
B) They conduct electricity but are not malleable.
C) They do not conduct electricity and are not shiny.
D) They react with acids and conduct heat.
14. The following diagram represents the Bohr-Rutherford model of an element.
Which of the following is true?
A) The element is located in period 1 and is an alkaline earth metal.
B) The element is located in period 1 and is an alkali metal.
C) The element is located in period 2 and is an alkali metal.
D) The element is located in period 2 and is an alkaline earth metal.
15. Four elements from the periodic table are described below.
Element A: It reacts vigorously with water and its electrons are distributed among three
energy levels.
Element B: It is located in Period 3 and used to disinfect or to kill bacteria.
Element C: Its electron configuration is
Science & Techno 10
June Exam Review Material World
Element D: Its outermost energy level is full and it could have 22 neutrons.
Complete the table below by indicating the chemical symbol and the name of the
chemical family for each of these elements.
Element Chemical
Symbol Chemical
Family Name
Element A
Na
Alkali metal
Element B
Cl
halogen
Element C
Mg
Alkaline earth
Element D
Ar
Noble gas
16. Which of the following states two properties of the elements in the halogen
family?
A) They are soft metals and highly reactive.
B) They do not conduct electricity and are not shiny.
C) They conduct electricity but are less reactive than alkali metals.
D) They are colourless in their natural state and are not chemically reactive
17. An element has the following characteristics:
• It has a metallic luster.
• It conducts electricity.
• It has 3 valence electrons.
• It is a metal
What is this element?
A) Aluminum
B) Lithium
C) Silicon
D) Sodium
Science & Techno 10
June Exam Review Material World
18. The table below gives the chemical symbols of four elements and provides space to
indicate the following characteristics: the number of valence electrons, the number of
energy levels, chemical reactivity (none, low or high) and the family number. Using the
periodic table, fill in the blank boxes in the table.
Li
C
Cl
Ne
1 valence
2 levels
7 valence; 3 levels
not reactive; VIII
Science & Techno 10
June Exam Review Material World
19.
Listed below are items of information pertaining to the Rutherford-Bohr model of
an atom of a chemical element.
1-The number of positive charges
2- The number of negative charges
3-The number of electron shells (energy levels)
4-The number of valence electrons
5-The atomic number
Which table correctly indicates the items of information pertaining to the inside
and outside of the nucleus?
A)
Inside the nucleus
1, 3 and 4
Outside the nucleus
2 and 5
B)
Inside the nucleus
1 and 5
Outside the nucleus
2, 3 and 4
Inside the nucleus
2, 3 and 5
Outside the nucleus
1 and 4
Inside the nucleus
2 and 4
Outside the nucleus
1, 3 and 5
C)
D)
Science & Techno 10
June Exam Review Material World
 Chapter on Molecules and Solutions
20. When Chlorine becomes an ion, what is its ionic notation?
a) Cl –
c) Cl +
b) Cl 2–
d) Cl 2+
21. When Sodium becomes an ion, what is its ionic notation?
a) Na –
c) S2–
b) Na+
d) S2+
22. When Aluminum becomes an ion, what is its ionic notation?
a) Al 3–
b) Al3+
c) Al13–
d) Al13+
23. When Neon becomes an ion, what is its ionic notation?
a) Ne –
b) Ne+
c) Ne8–
d) None of the above
Science & Techno 10
June Exam Review Material World
24. Draw the Rutherford-Bohr AND the Lewis model for the following ions:
a) Na+
b) N3-
Na+:
11p
N3- 7p
2e)8e)
B3+ 5p
2e)
c) B3+
2e)8e)
25. A student makes 75 mL of a 12.5 g/L salt solution. How much salt was used?
m = CV
= 12.5g/L (0.075 L) =
a) 0.17 g
b) 0.94 g
c) 6 g
d) 937 g
Science & Techno 10
June Exam Review Material World
26.
A salt solution has a concentration of 6.1 % m/v. Which concentration below
does this equate to?
6.1 % m/v means 6.1 g/100 ml = 6100 mg/0.1 L = 61000 ppm
a) 0.61 g/mL
b) 0.61 g/L
c) 6.1 g/L
d) 61 000 ppm
27. A C6H12O6 solution has a concentration of 215 ppm. Which concentration below does
this equate to?
215 ppm means 215 mg/L = 0.215 g/L
28.
a) 0.002 15 g/mL
c) 0.215 % m/v
b) 0.215 g/L
d) 2.15 % m/v
A KOH solution has a concentration of 0.05 g/mL. Which concentration below
does this equate to?
0.05 g/mL = 50 mg/0.001 L = 50 000 ppm
To get %, we need to know how much would be in 100 ml
= 0.05 g /ml *100 ml
=
a) 5 % m/v
b) 50 ppm
c) 500 g/L
d) 5000 ppm
By the way, 0.05g/L is also equal to 50 g/L. Show why.
Science & Techno 10
June Exam Review Material World
29. Matthew has 4 different salt solutions.
Solution A has a concentration of 0.0034 g/mL = 3.4mg/0.001L = 3400 ppm
Solution B has a concentration of 0.4 g/L
= 400 mg/L = 400 ppm
Solution C has a concentration of 0.42 % m/v = 0.42 g/100 ml = 420mg/0.1 L =
4200 ppm
Solution D has a concentration of 435 ppm
Which one has the highest concentration?
a) Solution A
c) Solution C
b) Solution B
d) Solution D
30. Sophie also has 4 different salt solutions.
Solution A has a concentration of 0.0034 g/mL
Solution B has a concentration of 0.4 g/L
Solution C has a concentration of 0.42 % m/v
Solution D has a concentration of 435 ppm
Which one has the lowest concentration?
a) Solution A
c) Solution C
b) Solution B
d) Solution D
31. Alex has 4 different NaOH solutions.
Solution A has a concentration of 0.2 g/mL
Solution B has a concentration of 19 g/L
Solution C has a concentration of 2.1 % m/v
Solution D has a concentration of 19 800 ppm
Science & Techno 10
June Exam Review Material World
Which list correctly places the solutions from least to most concentrated?
a) A, C, D, B
b) A, C, B, D
c) B, D, C, A
d) B, D, A, C
Science & Techno 10
June Exam Review Material World
32. Many commercial products are aqueous solutions.
a) A variety of orange juice contains 26g of carbohydrates per 250 mL serving.
What is the concentration of carbohydrates in % m/v?
26g/250 ml *100% = 10.4%
b) A 500mL bottle of isopropyl alcohol, better known as rubbing alcohol,
contains 350 mL of alcohol. What is the alcohol concentration in % v/v?
350g/500 ml *100% = 70%
33. During a lab experiment, you are asked to prepare 200 mL of a 12% m/v
saltwater solution.
Describe a procedure that will allow you to make the solution.
200 ml * 12g/100 ml = 24 g
1. Weigh 24 g of saltwater
2. Dissolve in a beaker of water
3. Transfer to a 200 ml volumetric flask.
4. Add water to line and mix.
Science & Techno 10
June Exam Review Material World
34. Alice frequently uses a white cleaning powder in her home. She wants to know
whether this substance is acidic, basic or neutral. In order to determine the pH of
this substance, what is the first thing that she must do?
A) Put a piece of blue litmus paper on the solid.
B) Put a piece of red litmus paper on the solid.
C) Verify whether the substance conducts electricity.
D) Dissolve a small amount of the solid in water.
35. Which of the following are acids?
1. NaCl
2. HCl
3. LiF
4. NH4OH
5. HI
6. HCH3CO2
7. KOH
8. CaCl2
A) 1, 5, and 8
B) 2, 5, and 6
C) 5, 6, and 8
D) 3, 4 and 7
Science & Techno 10
June Exam Review Material World
36. Which of the following are bases?
1. NaOH
2. HCl
3. LiF
4. NH4OH
5. BeO
6. HI
7. KOH
8. CaCl 2
A) 1, 4, and 7
B) 2, 3, and 8
C) 3, 5, and 6
D) 1, 3, and 7
37. Which of the following describes a neutral salt?
A) A solution that does not conduct electricity and that does not change the colour
of litmus paper.
B) A solution that does conduct electricity and that does not change the colour of
litmus paper.
C) A solution that does conduct electricity and turns litmus paper red.
D) A solution that does conduct electricity and turns litmus paper blue.
Science & Techno 10
June Exam Review Material World
38. Use the table below to determine which statement is TRUE.
A) When a strong acid is used with indicator 1, the solution turns blue.
B) A neutral solution will be colourless when indicator 2 is used.
C) When a strong base is used with indicator 3, the solution turns red.
D) When the solution is a weak acid and indicator 4 is used, the solution turns red.
39. Scientific studies show that the number of aquatic species declines when a lake
becomes more acidic. The pH of the water in four lakes was measured to determine
whether aquatic species are threatened. The table below lists the pH values obtained:
Lake
1
2
3
4
pH
4.2
6.5
7.0
7.5
Which of these lakes poses the greatest threat to aquatic species?
A) Lake 1
B) Lake 2
C) Lake 3
D) Lake 4
Science & Techno 10
June Exam Review Material World
40. In order to classify three unknown solutions as acids, bases or salts, you have
been given the following information:
Solution information
Electrical conductivity
Reaction of blue litmus paper
Reaction of red litmus paper
1
yes
Turns red
Stays red
2
yes
Stays blue
Stays red
3
Yes
Stays blue
Stays blue
On the basis of this information, how do you classify the three solutions?
A) Solution 1: Acid
Solution 2: Base
Solution 3: Salt
B) Solution 1: Acid
Solution 2: Salt
Solution 3: Base
C) Solution 1: Base
Solution 2: Acid
Solution 3: Salt
D) Solution 1: Base
Solution 2: Salt
Solution 3: Acid
41. A solution of NaOH is tested, and its pH is recorded. Which product below could
be used to neutralize this solution?
a) HCl
b) Mg(OH)2
c) NaCl
42. Which of the following pH values is alkaline?
a) 5
b) 6
c) 7
d) H2O
d) 8
43. An apple has a pH of 3, and a carrot has a pH of 5. How many times is the apple
more acidic than the carrot?
5-3 = 2, so apple is 102 = 100 times more acidic.
Science & Techno 10
June Exam Review Material World
44. To check the electrical conductivity of certain liquids, a student used a
conductivity apparatus equipped with a light bulb.
Using the table of information, determine which substances are electrolytes.
Substances
Observations
HCl
CH3OH
MgCl2
NaOH
Ca(OH)2
CCl4
Bright light
No light
Faint light
Bright light
Faint light
No light
A) CH3OH and CCl4
B) CH3OH, NaOH and Ca(OH)2
C) HCl, MgCl2 and CCl4
D) HCl, MgCl2, NaOH and Ca(OH)2
45. In a neutralization reaction:
A) two acids react to form water.
B) water and a salt react to form an acid and a base.
C) an acid and a salt react to form water and a base.
D) an acid and a base react to form a salt and water.
Science & Techno 10
June Exam Review Material World
46. Complete the following dissociation equation and label each as either acid, base
or salt.
a) HCl 
H+ + Cl-
b) Mg(OH)2  Mg2+ + 2 OHc) BCl3 
type of electrolyte:_acid
type of electrolyte: base
This gas won’t break up into ions in water; it reacts instead.
47. a) A student has to choose a test in order to distinguish whether a solution is an
acid, base or salt. He chooses the electrical conductivity test. Describe why this
would (or would not) be an appropriate test.
Bad test. All of the above conduct electricity in solution, so it won’t help you
distinguish between them.
b) Complete the neutralization reaction:
NaOH + HNO3  NaNO3 + H2O
Science & Techno 10
June Exam Review Material World
 Chapter on Different Forms of Energy
48. What is the law of conservation of energy?
Energy can be transformed from one form into another, but it cannot be
created or destroyed.
49. Wind turbines generate power for all
communities in Texas. How does a
wind turbine transform energy?
The wind spins the blades of a
turbine which through a gearbox
spin the magnets of a generator
When these move, alternating
current electricity in copper coils
within the core starts to flow.
50. What energy transformation takes
place in a flashlight that uses
batteries?
Chemical to electrical to light
energy.
Science & Techno 10
June Exam Review Material World
51. What is the percent efficiency of a light bulb that is supplied with 2000 J of
energy and 300J is used to give off light?
100%
2000 − 300
∗ 100% = 85%
2000
52. A television takes 1000 J of energy and gives off 150J as heat. What is the percent
efficiency of the television?
1000 − 150
∗ 100% = 85%
1000
53. A hummer uses 5000 J of energy and 3000 J is given off as pollution while the rest
is converted to mechanical energy to make the car move. What is the percent
efficiency of the hummer?
40%
Science & Techno 10
June Exam Review Material World
54. A student is heating two beakers of water. In beaker A, there is 500 mL of water
at 50⁰C while beaker B contains 100mL of water at 100⁰C. In which beaker is the
heat energy the greatest? Explain your answer.
Beaker A
Beaker B
Answer: beaker A
It’s a bit of an unfair question that goes beyond the scope of the course.
Although heat depends on both mass and temperature(part of the course), and
although there is 5 times as much mass at 50 oC , 100 oC does not represent
twice the kinetic energy of molecules. To figure that out, you need to convert to
the Kelvin scale by adding 273. So at 100 C, there is only 373/323 times as much
movement but only 1/5 th of the mass, so there is less heat in beaker B.
55. Julia goes jogging three times a week. On those days, she eats two slices of whole
wheat bread with oatmeal and a glass of milk. She completes her meal with a piece
of fruit, often an apple. An hour after her meal, she runs 12 km.
a) What form of energy is contained in these foods?
chemical
b) What form of energy is the source of the energy stored in the food Julia eats?
solar
Science & Techno 10
June Exam Review Material World
c) As Julia runs, the energy from the food is transformed into other forms of energy.
Name these other forms of energy and explain your answer.
Heat, mechanical energy and other forms of chemical energy as the food compounds
are converted into other molecules.
 Chapter on Changes in Matter
56. Consider the following chemical reaction:
2 NaCl + Ca(OH)2  CaCl2 +2 NaOH
If the mass of NaCl reacted is 191 grams and that of Ca(OH)2 is 74 grams
then 80 grams of NaOH is produced. What mass of CaCl2 is produced?
191 + 74 -80 = 185 g, but this question is badly constructed because they are not
reacting in stoichiometric ratios.
It should have read:
If the mass of NaCl reacted is 191 grams and that of Ca(OH)2 is 120 grams
then 130 grams of NaOH is produced. What mass of CaCl2 is produced?
The answer would have been 191 + 120 – 130 = 181 g
Science & Techno 10
June Exam Review Material World
57. Which part of the triangle of fire are firefighters tackling in each of the following
situations? Explain your answers.
a) Firefighters at an airport pour foam onto a pool of flammable liquid spilled by an
airplane in distress.
The fire is being choked so the oxidizer(often oxygen) is being removed.
b) Firefighters spray water onto the roofs and sides of two houses next to a blaze.
Heat
d) During a forest fire, firefighters begin clear-cutting a threatened area. They
cut a 50-m-wide stretch of forest a few kilometres ahead of the fire.
Fuel is being eliminated.
58. Which of the following is the chemical formula for respiration?
a) C3H8 + 5O2  3CO2 + 4H2O
b) C6H12O6 + 6O2 6CO2 + 6H2O
c) 6CO2 + 6H2O  C6H12O6 + 6O2
d) 3CO2 + 4H2O  C3H8 + 5O2
59. Which of the following is a combustion chemical equation?
a) C3H8 + 5O2  3CO2 + 4H2O
b) C6H12O6 + 6O2 6CO2 + 6H2O
c) 6CO2 + 6H2O  C6H12O6 + 6O2
d) 3CO2 + 4H2O  C3H8 + 5O2
Science & Techno 10
June Exam Review Material World
60. Which of the following is the chemical formula for photosynthesis?
a) C3H8 + 5O2  3CO2 + 4H2O
b) C6H12O6 + 6O2 6CO2 + 6H2O
c) 6CO2 + 6H2O  C6H12O6 + 6O2
d) 3CO2 + 4H2O  C3H8 + 5O2
61. During a chemical reaction, 15 g of hydrochloric acid (HCl) reacts with 3.7 g of
aluminum (Al) to produce 18 g of aluminum chloride (AlCl3) and some hydrogen
gas (H2) is released. The balanced equation for this reaction is as follows:
6 HCl + 2 Al → 2 AlCl 3 + 3 H2
What mass of hydrogen gas was released? 15 + 3.7 – 18 = 0.7 g of hydrogen.
62. Balance the following chemical equations and draw a particle model for each.
a) C6H12O6
b) 2 N2
+ 6 O2
+
O2
→
→ 2 N2O
6 CO2 +
6 H2O
Science & Techno 10
June Exam Review Material World
+
c) CO2
d) 2 Al +
+
2 KOH
3H2SO4
e) 2 H2O2 →
f) NH4NO2 →
→
2H2O +
N2
→
K2CO3
Al2(SO4)3
O2
+ 2H2O
+
H 2O
+ 3H2
Science & Techno 10
June Exam Review Material World
 Chapter on Electricity and Magnetism
63. Which object would be most attracted to the object to the right?
D
a)
+ –
b)
–
d)
c)
+ –
–
+
+ –
+
– +
– –
–
+ +
64. A wire is attached to a 20V power source. An ammeter reads a current of 5A.
What is the resistance of the wire?
V = IR
R = V/I = 20/5 = 4 Ω
a) 0.25 Ω
b) 25Ω
c) 4Ω
d) 100Ω
65. A wire with a resistance of 90 Ω is hooked up to a 9 V battery. What current will it
draw?
a) 810 A
b) 99A
c) 10A
d) 0.1A
66. An appliance draws 4A of current when it is attached to a 20V battery. It is used
for 1 minute. How powerful is the appliance?
P = VI = 20(4) = 80 W
a) 5Ω
b) 80 W
c) 80J
d) 4800 J
Science & Techno 10
June Exam Review Material World
67. A lamp is plugged into a 100V outlet, and has a resistance of 20Ω. It is on for 30
minutes. How powerful is the lamp?
V=IR
I = V/R = 100/20 = 5 A
P=VI
=100(5) = 500 W
a) 5A
b) 500 W
c) 2000W
d) 3 600 000J
68. A wire is attached to a variable power source, and the potential difference and
current readings are shown below.
Current (A)
5
1
5
10
15
20
Potential
difference (V)
a) What is the value of the resistance of this wire? (show your work)
conductance = slope =
resistance =
1
∆𝐼
∆V
𝑐𝑜𝑛𝑑𝑢𝑐𝑡𝑎𝑛𝑐𝑒
=
8−2
20−5
=
6
15
= 15/6 =2.5 Ω
b) How conductive is the wire? (show your work)
conductance = slope =
∆𝐼
∆V
=
8−2
20−5
=
6
15
S
Science & Techno 10
June Exam Review Material World
c) If this same wire were attached to a 100 V power source, what current would
flow through the wire? (show your work)
V=IR
A
100=I(2.5)
I = 40 A (huge!)
Current (A)
B
69. Which of the following wires is the best conductor?
a)
b)
c)
d)
A
B
C
D
C
D
Potential
difference (V)
70. A radio uses 4 x 1.5 V batteries and draws a current of 10A. If the radio is used for
5 minutes, how much energy does it use?
P = VI = (4*1.5 J/C)(10 C/s) = 60 J/s or 60 W
E = Pt = 60J/s(300 s) = 18 000 J
a) 15W
b) 60 W
c) 300J
d) 18 000 J
71. An oven is plugged into a 200V outlet and has a resistance of 100Ω. It is used for
1 hour. How much energy does it use?
a) In Joules?
E = VIt = (V2/R)t = 2002/100* 3600s = 1 440 000 J
Science & Techno 10
June Exam Review Material World
b) In kW•h
P=V2/R = 2002/100 = 400W = 0.400kW
E = Pt
=0.400 kW* 1 h = 0.400 kWh
72. Which of the following does NOT affect the conductance of a wire?
a) Length of the wire
b) Material of the wire
c) Potential difference across the wire
d) Thickness of the wire
Voltage affects the current but not its conductance
73. Given this circuit:
L2
S1
L1
S2
Which switch(es) would have to be on to turn L1 on?
a) S1 only
b) S2 only
c) Both S1 and S2
Science & Techno 10
June Exam Review Material World
d) L1 will be on without either switch being on.
74. Given this circuit:
L2
A
S1
C
L1
S2
B
Where would you add another switch to allow you to turn L2 on or off without
affecting L1?
a) A
b) B
c) C
d) None of the above
Science & Techno 10
June Exam Review Material World
75. Given this circuit:
Which of the following statements is TRUE?
a) When S1 is on and S2 is off, L2 will go on.
b) When S1 is off and S2 is on, L1 will go on.
c) When S1 is on and S2 is off, L1 will go on.
d) When S1 is on and S2 is off, neither light will go on.
76. Given this circuit:
What will happen when S1 is closed and S2 is open?
a) L1 will be on and L2 will be off
b) L1 will be off and L2 will be on
c) Both lights will be on
d) Both lights will be off
Science & Techno 10
June Exam Review Material World
77. Given this circuit:
What will happen when S1 is open and S2 is closed?
a) L1 will be on and L2 will be off
b) L1 will be off and L2 will be on
c) Both lights will be on
d) Both lights will be off
78. Given this circuit:
A
A switch is added at point ‘A’. If the switch is open, what will happen?
a) L1 will be on and L2 will be off
b) L1 will be off and L2 will be on
c) Both lights will be on
d) Both lights will be off
Science & Techno 10
June Exam Review Material World
79. Which of the following correctly shows the magnetic field lines of a bar magnet?
a)
b)
N
S
c)
N
S
N
S
d)
N
S
80. Which one of the compasses below is correctly indicating the magnetic north? D
a)
b)
N
N
S
c)
N
N
S
N
S
d)
N
S
N
N
81. If a compass were placed at the following position, in which direction would it
point? D
N
Compass
placed here
S
a)
c)
N
N
b)
d)
N
N
Science & Techno 10
June Exam Review Material World
82. If a compass were placed at the following position, in which direction would it
point?B Opposites attract
N
S
Compass
placed here
a)
c)
N
b)
N
d)
N
N
83. Current flowing through a live wire creates a magnetic field. If a compass is
placed right on top of the wire in position indicated below, in which direction
would the compass point? B (use left hand rule; let your thumb from left hand
point left where the compass is because the electrons are coming from the
negative (short bar)
a)
c)
N
b)
d)
N
N
Science & Techno 10
June Exam Review Material World
84. Current flowing through a live wire creates a magnetic field. If a compass is
placed right on top of the wire in position indicated below, in which direction
would the compass point? B
a)
b)
c)
d)
N
N
85. Given the current carrying wire below, and the compass which is placed directly
on top of the wire,
+
–
Compass
placed here
in which direction will the compass point?
a)
N
b)
D
N
N
Science & Techno 10
June Exam Review Material World
c)
d)
N
86. Given the current carrying wire below, and the compass which is placed directly
+
on top of the wire,
–
Compass
placed here
in which direction will the compass point? C
a)
c)
b)
N
d)
N
N
N
87. A vertical circuit is set up, and a piece of cardboard is placed perpendicular (90°)
to the wire
A
D
B
C
In which direction will the compass at B point? D
a)
b)
N
N
Science & Techno 10
June Exam Review Material World
c)
d)
N
N
88. A vertical circuit is set up, and a piece of cardboard is placed perpendicular (90°)
to the wire
A
D
B
C
In which direction will the compass at C point?A
a)
b)
N
c)
N
N
d)
N
Science & Techno 10
June Exam Review Material World
89. A vertical circuit is set up, and a piece of cardboard is placed perpendicular (90°)
to the wire
A
D
B
C
In which direction will the compass at D point?B
a)
b)
N
c)
N
N
d)
N
90. Marc opens 4 lamps in his house and keeps them all on for 3 hours. The
power rating is written on each lamp:
Lamp A: 500 W
Lamp B: 2 kW
Lamp C: 200 W
Lamp D: 4 kW
Which lamp would cost him the most amount of money for the three hour
period?
a) Lamp A
b) Lamp B
c) Lamp C
d) Lamp D
Science & Techno 10
June Exam Review Material World
91.Given this circuit:
A
A switch is added at point “A” . If the switch is open, what would happen?
a) L1 will be on and L2 will be off.
b) L1 will be off and L2 will be on.
c) Both L1 and L2 will be off.
d) Both L1 and L2 will be on.
92.Which of the following wires would provide the best conductance?
a) Length: 2m ; thickness 10 mm ; material: copper
b) Length 3 m; thickness 5 mm ; material: copper
c) Length 3 m; thickness 15 mm ; material: nichrome
d) Length 3 m; thickness 10 mm; material: nickel
Science & Techno 10
June Exam Review Material World
93. What is the difference between the three methods in charging an object: friction,
conduction and induction?
Method
Friction
Conduction
(touching)
Induction
(not touching)
Before
During
Two neutral objects Electrons will
transfer from one
to the other
After
One will be (+);
other (-)
Once charged, one
neutral
If there’s enough
positive charge in
the one on the left,
there will not be
enough electrons to
neutralize it, and
both will be
positive.
They will go back to
theoriginal.
++
Once charged, one
neutral
+
Electrons will flow
from neutral to
positive charge
The negatives will
move to the left
side of the neutral
sphere because
they are attracted
to the positive
sphere.
Science & Techno 10
June Exam Review Material World
94. In the laboratory, a student was given an acetate ruler, a cotton cloth and the
following electrostatic series.
Capacity to
Rubber
gain electrons
Cotton
Silk
Wool
Acetate
The diagram below shows the distribution of the charges in each substance.
+
+
+
+
Acetate Ruler
+
+
+
+
Cotton Cloth
The student rubbed the acetate ruler with the cotton cloth.
a) Taking into account the initial diagram, draw the charges in the acetate ruler and
in the cotton cloth after they were rubbed together.
Will lose electrons
Acetate Ruler
will gain electrons
Cotton cloth
b) State the charge on the acetate ruler and the charge on the cotton cloth after
they were rubbed together. Justify your answer.
Acetate = (+)
Cotton cloth = (-)
___________________________________________________________________
____________________________________________________________________
Science & Techno 10
June Exam Review Material World
95. You rub a balloon on your hair in order to stick the balloon on the wall.
Which of the following statements is TRUE?
A) When rubbed together, both the balloon and your hair become positively
charged.
B) When rubbed together, both the balloon and your hair become negatively
charged.
C) When rubbed together, the balloon remains neutral and your hair becomes
negatively charged.
D) When rubbed together, the balloon becomes negatively charged and your
hair becomes positively charged.
96. Silk and glass are two electrically neutral materials. Silk can be represented by
+++
++++
and glass by
.
After these materials are rubbed together, silk becomes negatively charged and glass becomes
positively charged.
Which of the following models may represent silk and glass after these materials have been
rubbed together?
A)
silk
glass
+++++++
B)
silk
glass
++++
+++
glass
++++
C)
+++
silk
D)
silk
+
glass
++++++
Science & Techno 10
June Exam Review Material World
97. We are given four spheres, A, B C and D. Sphere A is positively charged and the
charges on spheres B, C and D are unknown.
The following diagram shows what happens to these spheres if we suspend them two by
two close to each other.
A
B
B
C
C
Given the diagram above, what are the charges on spheres C and D?
A)
Sphere C is positively charged and sphere D is negatively charged.
B)
Sphere C is positively charged and sphere D is positively charged.
C)
Sphere C is negatively charged and sphere D is negatively charged.
D)
Sphere C is negatively charged and sphere D is positively charged.
D
Science & Techno 10
June Exam Review Material World
98. Four charged spheres A, B, C and D are suspended from wires.
The following diagrams show what happens when these spheres are suspended in pairs
close to each other.
A
B
A
C
B
D
Spheres A and D are suspended close to each other, as are spheres B and C.
Which of the following pairs of diagrams correctly shows what will happen to these
spheres?
A)
A
D
A
D
B
C
B)
B
C
B
C
C)
A
D
A
D
D)
B
C
Science & Techno 10
June Exam Review Material World
99. You are asked to confirm the following hypothesis:
Hypothesis: IF a plastic ruler is rubber with a wool cloth, THEN the ruler becomes
negatively charged.
You know the following as a fact:
When you rub a balloon on your hair, the balloon becomes negatively charged.
You have the following materials:
- 1 plastic ruler
- 1 balloon
- your hair
- 1 piece of wool
Explain the produce you would use to do this. In your explanation, list the steps
involved in this procedure and describe the way the charged objects will behave after
all these steps have been performed.
STEPS INVOLVED:
1. Rub ruler with wool cloth.
2. Rub balloon with hair.
3. Move ruler towards balloon.
4. Move wool towards hair.
THE WAY THE CHARGED OBJECTS WILL BEHAVE:
If hypothesis is correct, then the hair-rubbed balloon(-) will be repelled by the ruler(-)
The hair(+) will also be repelled by the wool. But the wool should attract the ruler, if
the hypothesis is correct.
Science & Techno 10
June Exam Review Material World
100. Consider the following experimental results:
A.
Two glass rods rubbed on silk repel each other.
B.
An ebonite rod rubbed on fur attracts a glass rod rubbed on silk.
C.
A piece of sulphur rubbed on flannel repels an ebonite rod rubbed on fur.
a)
What can you conclude from statement A about the charges on the glass
rods?
They have the same charge.
b)
What can you conclude from statement B about the charges on the
ebonite rod and the glass rod?
They have opposite charges.
c)
What will happen if the glass rod in statement A is placed near the piece of
sulphur in statement C? Explain your answer.
They will attract. The sulphur repelled ebonite, implying that the ebonite and
glass have the same charge.
2 Possibilities, but same result: glass(+) , ebonite (-), sulphur(-) , so glass and
sulphur attract
Or glass(-) , ebonite (+), sulphur(+) , so glass and sulphur still attract
Science & Techno 10
June Exam Review Material World
101. Draw lines to connect the elements in the three columns.
Definition
a) current
intensity
2A
•
•
b) electrical
power 3B
•
•
c) potential
difference
1C
•
•
1. the amount of
energy
transferred
between two
points in an
electrical circuit
2. the number of
electrical charges
that flow past a
given point in a
circuit within a
given time
3. the amount of
energy released
per unit of time
•
Unit of
measurement
• A. ampere
•
• B. watt
•
• C. volt
102. Mr. Lane uses an electric mower to cut his grass. The house is 10 m from the street, and
the back yard is 30 m long. This summer, you are cutting Mr. Lane’s grass for him. He
explains that, to do the front lawn, he plugs a 15-m extension cord into an outlet on the
outside of the house. For the back yard, he needs a 30-m extension cord, also plugged into
an outside outlet. He tells you that his mower cuts the front lawn better than the grass at the
back, but he does not understand why.
a)
How would you explain the difference in the mower’s efficiency?
The longer wire increases resistance, lowers current and reduces power.
Science & Techno 10
June Exam Review Material World
b) You talk to your father about Mr. Lane’s problem. He tells you that the next time you cut
the grass he will lend you a 30-m extension cord to do the lawn behind the house. You
notice that, with this extension cord, there is no longer any difference between the
mower’s efficiency on the front and back lawns. How do you explain this improvement?
This enforces the idea that the length of the cord was the cause.
103. A soft iron rod is magnetized with a bar magnet, as shown in the diagram below. Identify
the poles of the iron rod.
N
S
104. Draw the position of the needle in each of the compasses placed near the magnets or wire
illustrated below.
a)
b)
N
S
N
S
Compass I
Compass II
+
–
c)
Compass III placed beneath the wire
105. Draw a magnetic field for each of the following examples
a)
N
S
N
S
Science & Techno 10
June Exam Review Material World
b)
N
c)
N
S
S
S
N
Science & Techno 10
June Exam Review Material World
106. An electric current flows through a straight wire and produces a magnetic field.
Which of the following diagrams correctly represents this magnetic field?
A)
+
B)
+
C)
D)
+
+
107. How must the ammeter and the voltmeter be connected?
A)
C)
V
Appliance
A
A
Appliance
V
Science & Techno 10
June Exam Review Material World
B)
Appliance
D)
V
A
Appliance
V
A
108. What are the requirements necessary for one object to be able to magnetize
another object?
One of the objects has to be a permanent magnet while the other one has to
be ferromagnetic.
109.What happens to the domains when an object gets magnetized?
Their magnetic fields align and as they “ cooperate” they act as much bigger and
stronger magnetic field.
110.Give two properties of magnetic field lines for magnetism.
• They never cross each other.
• The more densely packed they are, the stronger the field is.
• A compass will align itself with the lines, revealing that the north end of the
compass is always “seeking” south.