Practice Test for Exam 2

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SCI 2201 Concepts in Science Pre-Test 2 (chap 5, 6, 8, 10)) name______________________
Formulas:
Voltage (Volts) = Current (Amps) x Resistance (Ohms)
Power (watts) = Current (amps) x Voltage (volts)
Wave velocity (m/s) = wavelength (m) x frequency (Hz)
1. How does a compass work?
2. Describe the properties of magnets.
3. What is the relationship between electricity and magnetism?
4. A student rubs a plastic drinking straw in its paper covering. The paper is then removed from
the straw. With the this straw, the student is able to pick up small bits of paper, and even particles
of salt and pepper.
a)
What is going on here?
b) Give another example that will illustrate the same phenomenon.
5.
Distinguish between the following concepts:
a. Electrical field, Magnetic field
b. Conductors, Insulators
c. Direct Current, Alternating Current
d. Current, Voltage, Resistance
e. Series Circuits, Parallel Circuits
6. compare the energy transformations that occur in an electrical motor and an electrical generator.
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7. Imagine you are given one flashlight battery, one strand of insulated electrical wire, and one
working flashlight bulb.
a) Diagram below an arrangement of these items that would cause the bulb to
light.
b) What is going on in the battery to cause the bulb to light?
c) What is going on in the wire to cause the bulb to light?
d) What is going on in the light bulb, to cause it to give off light?
_____8. The current through a 10 ohm resistor connected to a 120-Volt power supply is
a. 1 A b. 10 A c. 12 A d. 120 A
_____ 9. A 10 ohm resistor had 5 Amps of current in it. What is the voltage across the resistor?
a. 5 V b. 10 V c. 15 V d. 20 V
_____ 10. The electric power of a lamp that carries 2 Amps at 120 Volts is
a. 1/6 W
b. 2 W
c. 60 W
d. 20 W
e. 240 W
11…The electromagnetic spectrum includes all kinds of waves that travel at the speed of light.
Regarding this continuum of light forms below:
Gamma Rays-----X-Rays------Ultraviolet--Visible Light--Infrared-----Microwaves------Radio
Waves
As we progress along this continuum, comparing each type of radiation from left to right,
a. Does wavelength tend to increase or decrease? _________________
b. Does frequency tend to increase or decrease? __________________
c. Does the energy tend to increase or decrease? __________________
12…How does light interact with a:
a. convex mirror (like the outwardly curved side view mirror or the bottom side of a
metal spoon?)
b. concave mirror (like the inwardly curved make-up mirror or the top side of a
metal spoon?)
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13…Describe the four properties of waves: wavelength, frequency, velocity, amplitude.
14…Distinguish between transverse and longitudinal waves.
15…A curious kiddo is observing sound when she is suppose to be taking a bath! She notices a
difference in the sound quality in three different situations:
a. tapping the top of the tub while she is sitting up, with her head
out of the water
b. tapping the top of the tub with her head submerged in the water
c. tapping the top of the tub with her ear pressed against the side of
the tub
She taps with the same force each time, but notices ask, “Why does it sound louder under water?”
How would you answer her? What can we learn about sound from this experience?
16. What is the “Doppler effect”?
17…What are “atoms”? What are “elements”? What are “compounds”?
18…Draw one Helium atom (atomic number 2) and
label the location and charge of a
proton, neutron, and electron.
_____ 19) Each vertical column in the periodic table corresponds to an
a. atomic period
b. atomic group
_____ 20) Each horizontal row in the periodic table corresponds to an
a. atomic period
b. atomic group
For the next three items, choose from the following types of chemical bonds:
a. covalent
b. ionic
c. metallic
_____21) What type of bond would you expect between Ca (atomic # 20) and Cl (atomic # 17)?
_____22) What type of bond would you expect between Si (atomic # 14) and O (atomic # 8)?
_____23) What type of bond would you expect between atoms of copper, Cu (atomic # 29)?
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24. How will the Na and Cl atoms interact to form a stable compound? Provide a brief
explanation supported by an atomic structure sketch.
25…How will the H and O atoms interact to form a stable compound? Provide a brief explanation
supported by an atomic structure sketch.
26…The white paste that lifeguards rub on their noses to prevent sunburn contains zinc oxide.
ZnO, as an active ingredient. Zinc oxide is produced by burning zinc sulfide in the following
chemical reaction:
2ZnS + 3O2 ---> 2ZnO + 2SO2
a)
b)
c)
d)
What is the coefficient for for sulfur dioxide?
What is the subscript for oxygen gas?
How many atoms of oxygen react?
How many atoms of oxygen appear in the sulfur dioxide molecules?
For the remaining questions, refer to the periodic table below. (Note that the transition metals in
the middle of the table are not shown.)
27. Color code the elements to distinguish metals, nonmetals, and metalloids.
---The dots associated with each element symbol represent the number of outer electrons that
each atom has. The elements in the final family or column (He, Ne, Ar, Kr, Xe, Rn) will not
interact with the other elements and are said to be stable. The other nonmetals will bond and
the metals will bond with nonmetals as well.
28…Propose a reason why magnesium forms Mg2+ ions and not Mg6- ions.
29…Some chemical formulas that you are familiar with are H2O, CO2, NaCl, CaCl2, MgO.
a. Classify these 5 compounds as either covalent or ionic.
b. Can you identify any pattern from the information on the periodic table above
that explains why these atoms form these compounds in these particular ratios?
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