Download 8th Grade Physical Science Final Study Guide

8th Grade Physical Science Final Study Guide
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Name ______________________________
What is the only method to break down compounds? _Chemical Change
Which process causes drops of water to appear on the outside of a glass of juice on a warm day?Condensation
Which kind of change adds energy to a substance? Chemical Change
Which type of elements are all poor conductors of heat and electric current? Non-metal
What is a pure substance that can not be separated into simpler substance by physical or chemical means called?
__Element____________________________________________________________________________________
6. The substances that dissolve in a solvent are called __Solute____________________________________________.
7. All atoms of the same element have the same atomic __Weight_____________, which can be found on the
periodic table.
8. Which metals are only found in nature combined with other elements because of their highly reactive nature?
___Alkali Metals______________________________________________________________________________
9. An object’s change in position over a period of time is called __Motion________________________________.
10. The speed of an object in a particular direction is its ___Velocity_________________________________________.
11. If a driver’s acceleration is positive, then the driver’s velocity is __________________________________________.
12. A _Force________________________________________ is a push or pull on an object.
13. The measure of the gravitational force exerted on an object is _Weight_____________________________________.
14. A falling object will stop accelerating when air resistance exactly matches the downward force of gravity, which is
___Terminal Velocity_________________________________________________________________________.
15. The tendency of all objects to resist any change in motion is called __Inertia______________________________.
16. Which type of lever places the load between the input force and the fulcrum? _2nd degree____________________
17. Which type of pulley is attached to something so it does not move? ___Fixed_______________________________
18. The work you do on a machine such as turning a screwdriver is called __Work Input_________________________.
19. A bar that pivots on a fulcrum is a __Lever___________________________________________________________.
20. ___________________________________ is the transfer of energy between two objects with different temperatures.
21. Differences in temperatures in liquids and gases result in __Convection_____________________________ currents.
22. ___Radiation_____________________________ is the way that the energy from the sun is transferred to the Earth.
23. When ice changes to liquid it________Absorbs_________________________________________________ energy.
24. When vapor condenses to a liquid, energy is ___Released______________________________________________.
25. The particles in a __Solid________________ do not overcome the attraction between them, so they vibrate in place.
26. The distance between two rarefactions that are next to each other is the___Wavelength_______________ of a wave.
27. The bouncing back of a ray of light, sound or heat when they ray hits a surface that it does not go through is called
____Reflection__________________________________________________________________________.
28. If a barrier or opening is the same size or smaller than the wavelength of an approaching wave, there will be a
__Greater_________________ amount of diffraction.
29. When two waves meet and cancel each other out, _Destructive Interference_________________ occurs.
30. The maximum distance a wave vibrates from its rest position is called its____Amplitude______________________.
31. When a wave curves or bends around a barrier, ___Diffraction____________________________________ occurs.
32. The frequency of a sound wave determines the ___Pitch______________________________________ of the sound.
33. The particles of the medium in a ___longitudinal________ wave vibrate back and forth along the path of the wave.
34. __Absorption___________________________ is the transfer of energy carried by light waves to particles of matter.
35. An electromagnetic wave that can cause sunburn is __radiation_________________________________________.
36. Light you can see is called ______Visible Light_____________________________________________________.
37. The opposition to the flow of electric charges is ____Resistance_________________________________________.
38. Lightning is a form of _______Electric Discharge___________________________________________________.
39. A(n) ___Electric Field_______________ is the region around a charged object where an
electric force is present.
40. As resistance goes up, current goes ________down_____________________________________________________.
41. An object’s __Mass_____________________ would be the same on the moon as it is on Earth, but not its weight.
42. If you poured three liquids (that don’t mix completely) into a beaker, how could you tell which one is the most dense?
It’s on the bottom
43. The explosion of fireworks is an example of what type of change? Chemical Change
44. Why are chemical properties harder to observe than physical properties? They are at the molecular level
45. Ground flour is an example of what type of change? Physical
46. Which unit would be best for describing the volume of mercury (liquid) used in an experiment? mL
47. The motion of a 150 g ball is more difficult to change than the motion of a 50 g ball because it has more__Mass____.
48. Which physical property of matter describes the relationship between mass and volume?
49. What property of matter (inertia, mass, volume, or weight) is demonstrated by the fact that you cannot fit any more
books onto a bookshelf that is already filled?
50. To change the mass of an object, what do you add or take away? Matter
51. How are the particles arranged in a solid?
52. Describe how the particles in a gas move. Quickly & Freely
53. How do the particles of water that evaporate from an open container differ from the particles that remain? They are a
gas.
54. The melting point of salt is the same as its ___Freezing___________________________________________ point.
55. The particles that make up different types of matter do not move at the _same____________________ speed.
56. Boiling point, melting point, and density are some of an element’s __Physical _______________ properties.
57. What is formed when particles of two or more substances are distributed evenly among each other? Solution
58. How is a compound different from a mixture? The molecules are chemically combined.
59. How could a sugar cube be dissolved more quickly in water? Crushed, increase temperature
60. An unidentified substance is a good conductor of electricity, shiny and malleable. It is probably a(n) Metal________.
61. A(n) _Metalloid___________________________is an element that has the properties of both metals and nonmetals.
62. A substance in which a solute dissolves is a(n) __Solvent_____________________________________________.
63. Why is muddy water not a solution? Because the dirt/mud can settle down.
64. What is a pure substance made of two or more elements that are chemically combined? Compound
65. How would you describe the size, density, and overall charge of a nucleus? Largest part of the atom, dense,
Positive charge
66. What is the smallest particle into which an element can be divided and still be the same substance? Atom
67. An atom of carbon with 6 protons, 6 electrons, and 6 neutrons would have a mass number of __12_______________.
68. In an atom, which particle has the least mass? Electron
69. A hydrogen atom with one proton in its nucleus has a(n) __Atomic Number____________________________ of
one.
70. Periodic law states that _Repeating chemical & physical properties of elements change periodically with the
elements’ atomic numbers.
71. The elements to the right of the zigzag line on the period table are called __Non- Metals______________________.
72. Most metals are __Solid______________________________ at room temperature.
73. The vertical column of elements on the periodic table is called a(n) _Group_____________________________.
74. What are most of the elements in the periodic table – metals /nonmetals/metalloids? Metals
75. What are the left-to-right rows on the periodic table called? Period
76. An explosive breaking rocks in a mine is an example of chemical __________________________________breaking.
77. What happens between chemical bonds when a new substance forms during a chemical reaction? Break &
Rearrange.
78. A calcium carbonate molecule has 1 calcium (Ca) atom, 3 oxygen (O) atoms, and 1 carbon (C) atom. What is the
chemical formula for calcium carbonate? CaCO3
79. State the law of conservation of energy. Energy is neither created nor lost in a closed environment
80. How many atoms are represented in the formula CaCO3? 5
81. In a chemical reaction, atoms are never/always gained or lost. Never
82. What is the reference point of an SUV driving past a jogger at a relative speed of 15 m/s compared to the jogger?
Jogger
83. What kind of force is acting on a swing hanging still from the porch roof? ___Balanced Force__________________
84. The main difference between speed and velocity is __Velocity is speed in a certain direction._______.
85. Velocity change vs. time best represents ___Acceleration___________________________ as presented on a graph.
86. The combination of all __Forces_______________________ acting on an object best determines the net force when
more than one force is acting on an object.
87. Net forces that equal 0 N are considered __Balanced___________________________________________________.
88. __Unbalanced ___ ____Forces_________ always cause a change in speed, direction, or both.
89. _______Friction______________________ is a force that opposes motion between two surfaces that are in contact.
90. Car tires moving a car forward are an example of when _Friction________________________________ is helpful.
91. Pouring sand on ice is/is not a way to reduce friction. Is Not
92. True/False: All matter has mass; all mass is affected by gravity. True
93. As the distance between two objects increases, the force of gravity between them _Decreases_________________.
94. True/False: Mass is described as remaining constant. False
95. Gravitational pull is greater/less between two objects that have greater masses.Greater
96. You would add/subtract the following to determine the net force:10 N north & 5 N south. What is the
answer?Subtract
97. The measure of the amount of matter is _Mass________________________________________________________.
98. Average speed is calculated by dividing _Total _____ __Distance_____ by _Total _______ __Time________.
99. When an object goes straight at a constant speed, there is no _Acceleration________________________________.
100. A student weighs 70 N on the moon (Moon’s gravity = 1/6 Earth’s gravity). What does he weigh on earth? 420N
101. Gravitational force is related to mass and distance is the law of __Universal Gravitation___________________.
102. If you have the starting velocity, final velocity and the time it takes to change the velocity, you can calculate an
object’s __Average Velocity_______________________________________.
103. The force of __Gravity_____________________________ is greater between two objects that have greater masses.
104. Mass is a measure of the amount of ____Matter____________________________________________ in an object.
105. If a baseball and a cannonball are dropped from the same height at the same time, which ball will hit the ground
first? Baseball/Cannonball/Both at same time Both at the same time
106. Projectiles accelerate in which direction? ___Downward__________________________________________
107. The reaction force of a chair you are sitting on is greater than/less than/equal to your weight. Equal to
108. When a bowling ball collides with a bowling pin, the momentum of the ball increases/decreases as the velocity
increases/decreases? Decreases / Decreases
109. If a moving boxcar gently collides with a boxcar at rest and the two boxcars move together, their combined
momentum will be greater than/less than/equal to the original momentum of the moving boxcar. Greater than
110. If an action force is a cue ball hitting a billiard ball, then the reaction force is __Billiard ball reacts against the cue
ball
111. The path of a crate sliding along flat ground is/is not an example of projectile motion. Is Not
112. If dropped at the same time from the same height, a tennis ball/a solid rubber ball/a solid steel ball would hit the
ground first. (Assume no air resistance) The same time
113. An empty shopping cart, pushed with a light force has more or less acceleration than a full shopping
cart pushed with a light force. Less Acceleration
114. A crumpled piece of paper hits the ground before a flat sheet of paper because there is more _Air Resistance___
___________________ on the flat sheet of paper.
115. _Gravity_________________________________ causes the path of a ball thrown horizontally to curve downward.
116. A pitched baseball gets its horizontal motion from __the hand that exerts a force on the ball___.
117. Which of Newton’s Laws best describes an ice skater at rest pushing against a sled at rest causing both the skater
and sled to move away from each other with different accelerations? 3rd Law (For every action there is an equal
and opposite reaction)
118. Which of Newton’s Laws best describes a sled sliding on a flat, icy surface with a constant velocity? 1st Law – On
object in motion tends to stay in motion at a constant speed and in the same direction.
119. What device makes work easier: changing the size or direction of the force? Machine
120. A school crossing guard raising a stop sign that weighs 10 N is an example of _Work_________________ being
done on an object.
121. If a barbell weighs 160 N, what other information do you need to calculate how much work it takes to lift it? The
distance it was lifted.
122. How does a ramp make lifting a heavy object easier? By increasing the distance over which the work was done.
123. The work output of a machine is always less than the work input, and the missing work is used to overcome the
__Friction___________________________________________ created by the machine.
124. A block and tackle pulley is an example of a _Compound Machine______________________________________.
125. When a machine increases the size of the force exerted, the distance must __Increase______________________.
126. In order to increase the mechanical advantage of a first-class lever, the __Fulcrum_________________ should be
moved closer to the load.
127. A doorknob is an example what type of simple machine? Wheel & Axle
128. Water boils at 212°F, which is equivalent to ____0______________ °C.
129. The hot air that you see rising from the pavement on a summer day is an example of __Convection_____________.
130. The transfer of thermal energy through a substance by direct contact is called _Conduction________________.
131. When a substance changes state, what happens to the substance? It changes from one form to another
132. If the particles of two substances have the same average kinetic energy, then the substances have __The same_____
temperatures.
133. The glass of a window pane feels cooler to the touch than the wood frame surrounding the glass. This is because
wood is a better _Insulator_________ than glass.
134. In which state of matter does water have the lowest average kinetic energy? Solid
135. In which state of matter do particles move fastest and with little effect on each other? Gas
136. What happens to a substance’s temperature during a change of state? Changes
137. If each has the same temperature, which object has the most thermal energy? large pan of water/tub of water/
small cup of water/small bowl of water Tub of water
138. An expansion joint in a bridge is an example of the __Thermal _________________________ expansion of a solid.
139. Particles in a _Liquid________________ state move fast enough to overcome some of the attraction between them,
and so can slide past one another.
140. Waves transfer _Energy_________________________________________________________________________.
141. If a wave is traveling at a certain speed and its frequency is halved, the wavelength would be _Doubled_________.
142. A section of a longitudinal wave where the particles are crowded together is called a _Compression ____________.
143. When the crests of one wave overlap the crests of another wave or waves, _Interference______________ occurs.
144. _Electromagnetic
______________________________________ waves can travel without a medium.
145. An ocean wave is an example of a __Transverse________________________________________________ wave.
146. The amplitude of a wave related to its __Volume_____________________________________________________.
147. Sound waves travel around corners better than light waves because sound waves _Bend______________________.
148. A wave with a frequency of 3 Hz moves at a rate of _3_________________waves per ___second______________.
149. The distance a single wave crest or trough travels in a set amount of time is the _Wave Speed_______________.
150. A vacuum is NOT a ___Medium _______________________________________________________________.
151. True/False: Air particles travel with sound waves. False
152. The speed of a sound depends on the ___Medium______________________________ through which it travels.
153. Which of the following represents the correct sequence of events?
A)
Sound waves pass from an area of hot air to an area of cold air; the speed of
the sound waves slows; sound waves travel from air into water; the speed of
the sound waves increases.
B)
Sound waves pass from an area of hot air to an area of cold air; the speed of
the sound waves increases; sound waves travel from air into water; the speed
of the sound waves increases.
C)
Sound waves pass from an area of hot air to an area of cold air; the speed of
the sound waves increases; sound waves travel from air into water; the speed
of the sound waves slows.
D)
Sound waves pass from an area of hot air to an area of cold air; the speed
of the sound waves slows; sound waves travel from air into water; the
speed of the sound waves slows.
154. A father pushing a laughing toddler on a swing will experience what happens to sounds due to the _Doppler Effect
155. ____Frequency_________________________ is the number of waves produced in a given amount of time.
156. The particles of a medium in a ___Transverse_________________ wave move perpendicular to the direction that
the wave is traveling.
157. A(n) __Electromagnetic_________________________________ wave can travel through empty space or matter.
158. Electromagnetic waves are produced by the vibration of a(n) __Electric_______ field and a(n) _Magnetic______
field together.
159. The electromagnetic spectrum is divided into regions by __Wavelength_______________________________.
160. ____White Light____________________________________is the entire range colors of visible light combined.
161. Colors of __Opaque_________________________________objects are determined by the color of light they
reflect.
162. When white light is refracted, the amount that the light bends depends on the light’s _wavelength______________.
163. __Refraction___________________________________separates white light into different colors.
164. Mixing red, green, and blue light an example of color__Color Addition_________________________________.
165. This type of electromagnetic waves cause the warmth you feel when you sit in the sun. __Infrared____________
166. What colors of light are reflected by an opaque black object and which are absorbed? None reflected – all
absorbed
167. ______Radio Waves___________________________________________ are used to broadcast television signals.
168. What 3 types of electromagnetic waves have shorter wavelengths than visible light? Radio, microwaves, infrared
169. What process happens when electrons move from one object to another by direct contact? Conduction
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171.
172.
173.
174.
The loss of static electricity as charges move off an object is _Electric __Discharge___________________.
The size of a current depends upon__its voltage_________________________________________________.
How many pathways are there for moving charges in a series circuit? One
The size of an electric force depends upon which two things__The amount___&__distance of each charge.
This method is involved when charges in an uncharged metal object are rearranged without direct contact with a
charged object _Induction______________________________________________________________________.
175. A__Cell_____________________________________________ generates electrical energy from chemical energy.
176. What is the third part of an electric circuit besides the wires and the load _Power Source_____________________.
177. What happens if you rub a glass rod with a piece of silk and the rod becomes positively charged?
178. Electric Current_______________________________ is the rate at which charges pass a given point.
179. Which of the following copper wires will have the least amount of resistance.
A) a short, thin wire
C) a long, thin wire
D) a long, thick wire
B) a short, thick wire
180. In what type of circuit should Pedro wire four bulbs so that all the bulbs shine as brightly as possible?
181-184 label this diagram.
a. Electrons
b. Neutrons
c. Nucleus
d. Protons
INTERPRETING GRAPHICS
Use the figure below to answer the following questions.
185. Which of these elements is the most metallic: K, Kr, Fe, Cu K
186. Which of these elements is the least metallic: V, Zn, Co, Se SE
187. Which element group has all nonmetals?
K, Ca, Sc
V, Cr, Mn
As, Se, Br
Se, Br, Kr
Refer to the figure below to answer the following questions.
188. The number beneath carbon indicates the __Atomic Mass____________________________________.
189. The number at the top is the ___Atomic Number_____________________________________.
INTERPRETING GRAPHICS
Use the graphic below to answer the following questions.
190. a. Coefficient
191. b. Subscript
192. c.
193. d. Product
e. Reactants
190-193 label a –e
Use the graph below to answer the following question.
Graph B
194. Graph B is a graph of a roller coaster car moving up a hill. What does the straight upward slope on Graph show?
Positive Acceleration
Use the graph below to answer the following questions.
195. During which 5-minute interval did Kyle achieve the greatest average speed?
A) Between 0 minutes and 5 minutes)
B) Between 5 minutes and 10 minutes
C) Between 10 and 15 minutes
D) Between 15 and 20 minutes
196. What may have happened in the time period between 10 and 15 minutes?
A) Ken probably ran faster.
C). Ken probably stopped to rest.
B) Ken ran backward,
D). Ken probably slowed down.
INTERPRETING GRAPHICS
Examine the table below and answer the questions that follow.
Approximate Speed of Sound Through Different Media
Medium
Speed (m/s)
Air at 0°C
331
Air at 20°C
344
Brick
3,628
Steel
5,064
Water
1,480
197. Based on the data in the table, what general conclusion can you draw about the speed of sound in solids, liquids, and
gases?
A). Sound travels fastest through solids, second fastest through liquids, and slowest through gases.
B). Sound travels fastest through liquids, second fastest through solids, and slowest through gases.
C). Sound travels fastest through gases, second fastest through liquids, and slowest through solids.
D). Sound travels the same speed in all states of matter.
198. According to the table, how does temperature affect the speed of sound through air?
A) As the temperature of the air increases, the speed of sound through air decreases.
B). As the temperature of the air decreases, the speed of sound through air increases.
C). As the temperature of the air increases, the speed of sound through air also increases.
D). Air temperature does not affect the speed at which sound travels.
INTERPRETING GRAPHICS
Use the diagram below to answer the following questions.
a.
b.
199. Diagram A shows four bulbs wired in a circuit. What would happen if one of the bulbs burned out?
They would all go out.
200. Diagram B shows four bulbs wired in a circuit. What would happen if one of the bulbs burned out?
The other three would stay lit.