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NDQ_016758
the average of a set of values is also called the mode.
a. true, b. false
b
Lesson: descriptive statistics Using Statistics to Describe a Sample: The girls in the picture above make up a small samplethere are only four of them. In scientific investigations, samples may include hundreds or even thousands of people or other objects of study. Especially when samples are very large, its important...
NDQ_016760
the mode of the set of measurements in question 8 is
a. 24.35 cm, b. 22.51 cm, c. 23.43 cm, d. 20.98 cm
d
Lesson: descriptive statistics Using Statistics to Describe a Sample: The girls in the picture above make up a small samplethere are only four of them. In scientific investigations, samples may include hundreds or even thousands of people or other objects of study. Especially when samples are very large, its important...
NDQ_016772
terms used to describe relative direction include
a. in, b. up, c. sideways, d. all of the above
d
Lesson: direction Introducing Direction: Direction can be described in relative terms, such as up, down, in, out, left, right, forward, backward, or sideways. Direction can also be described with the cardinal directions: north, south, east, or west. On maps, cardinal directions are indicated with a compass rose. You c...
NDQ_016775
the direction of motion is a vector.
a. true, b. false
b
Lesson: direction Introducing Direction: Direction can be described in relative terms, such as up, down, in, out, left, right, forward, backward, or sideways. Direction can also be described with the cardinal directions: north, south, east, or west. On maps, cardinal directions are indicated with a compass rose. You c...
NDQ_016780
if you are facing north, then east is to your
a. left, b. right, c. back, d. none of the above
b
Lesson: direction Introducing Direction: Direction can be described in relative terms, such as up, down, in, out, left, right, forward, backward, or sideways. Direction can also be described with the cardinal directions: north, south, east, or west. On maps, cardinal directions are indicated with a compass rose. You c...
NDQ_016794
english units of distance include the
a. mile, b. square mile, c. mile per hour, d. all of the above
a
Lesson: distance What Is Distance: Distance is the length of the route between two points. The distance of a race, for example, is the length of the track between the starting and finishing lines. In a 100-meter sprint, that distance is 100 meters. SI Unit for Distance: The SI unit for distance is the meter (m). Sho...
NDQ_016797
a millimeter is longer than a centimeter.
a. true, b. false
b
Lesson: distance What Is Distance: Distance is the length of the route between two points. The distance of a race, for example, is the length of the track between the starting and finishing lines. In a 100-meter sprint, that distance is 100 meters. SI Unit for Distance: The SI unit for distance is the meter (m). Sho...
NDQ_016798
a yard is closest in distance to a
a. millimeter, b. centimeter, c. kilometer, d. meter
d
Lesson: distance What Is Distance: Distance is the length of the route between two points. The distance of a race, for example, is the length of the track between the starting and finishing lines. In a 100-meter sprint, that distance is 100 meters. SI Unit for Distance: The SI unit for distance is the meter (m). Sho...
NDQ_016800
to measure distance in si units, you could use a meter stick.
a. true, b. false
a
Lesson: distance What Is Distance: Distance is the length of the route between two points. The distance of a race, for example, is the length of the track between the starting and finishing lines. In a 100-meter sprint, that distance is 100 meters. SI Unit for Distance: The SI unit for distance is the meter (m). Sho...
NDQ_016803
the doppler effect can occur when the
a. sound source is moving and the listener is stationary, b. listener is moving and the sound source is stationary, c. sound source and listener are moving together, d. two of the above
d
Lesson: doppler effect What Is the Doppler Effect: The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. (It can also occur when the sound source is stationary and the listener is moving.) The Figure 1.1 shows how the ...
NDQ_016804
sound waves from a police car siren move away from the car in all directions.
a. true, b. false
a
Lesson: doppler effect What Is the Doppler Effect: The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. (It can also occur when the sound source is stationary and the listener is moving.) The Figure 1.1 shows how the ...
NDQ_016805
sound waves that are closer together have a lower frequency.
a. true, b. false
b
Lesson: doppler effect What Is the Doppler Effect: The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. (It can also occur when the sound source is stationary and the listener is moving.) The Figure 1.1 shows how the ...
NDQ_016806
as the frequency of sound waves gets lower, a listener perceives the sound to have a higher pitch.
a. true, b. false
b
Lesson: doppler effect What Is the Doppler Effect: The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. (It can also occur when the sound source is stationary and the listener is moving.) The Figure 1.1 shows how the ...
NDQ_016807
a police car is speeding north with its siren blaring. the sound waves from the siren increase in frequency
a. north of the car, b. south of the car, c. in all directions around the car, d. none of the above
a
Lesson: doppler effect What Is the Doppler Effect: The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. (It can also occur when the sound source is stationary and the listener is moving.) The Figure 1.1 shows how the ...
NDQ_016808
if you are standing a few blocks north of the police car in question 6, how does its siren sound to you as the car gets closer to your location?
a. the sirens pitch gets higher, b. the sirens pitch gets lower, c. the sirens pitch gets lower and then higher, d. the sirens pitch does not change
a
Lesson: doppler effect What Is the Doppler Effect: The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. (It can also occur when the sound source is stationary and the listener is moving.) The Figure 1.1 shows how the ...
NDQ_016810
after the police car in question 6 passes your location, how does the siren sound to you?
a. the sirens pitch gets higher, b. the sirens pitch gets lower, c. the sirens pitch gets lower and then higher, d. the sirens pitch does not change
b
Lesson: doppler effect What Is the Doppler Effect: The Doppler effect is a change in the frequency of sound waves that occurs when the source of the sound waves is moving relative to a stationary listener. (It can also occur when the sound source is stationary and the listener is moving.) The Figure 1.1 shows how the ...
NDQ_016813
which shape of magnet does magnet earth resemble?
a. horseshoe magnet, b. bar magnet, c. disc magnet, d. none of the above
b
Lesson: earth as a magnet Earths Magnetic Poles: Imagine a huge bar magnet passing through Earths axis, as in the Figure 1.1. This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts t...
NDQ_016815
the place generally referred to as earths magnetic north pole is located closest to
a. 90 degrees north latitude, b. 80 degrees north latitude, c. 70 degrees north latitude, d. 60 degrees north latitude
b
Lesson: earth as a magnet Earths Magnetic Poles: Imagine a huge bar magnet passing through Earths axis, as in the Figure 1.1. This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts t...
NDQ_016816
earth has two north poles and two south poles.
a. true, b. false
a
Lesson: earth as a magnet Earths Magnetic Poles: Imagine a huge bar magnet passing through Earths axis, as in the Figure 1.1. This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts t...
NDQ_016818
which of the following statements about earths magnetic field is false?
a. it extends outward from earth in all directions, b. it is strongest at the equator, c. its lines of magnetic force converge at the poles, d. none of the above
b
Lesson: earth as a magnet Earths Magnetic Poles: Imagine a huge bar magnet passing through Earths axis, as in the Figure 1.1. This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts t...
NDQ_016819
a compass needle always points to earths geographic north pole.
a. true, b. false
b
Lesson: earth as a magnet Earths Magnetic Poles: Imagine a huge bar magnet passing through Earths axis, as in the Figure 1.1. This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts t...
NDQ_016820
the like poles of two magnets always attract each other.
a. true, b. false
b
Lesson: earth as a magnet Earths Magnetic Poles: Imagine a huge bar magnet passing through Earths axis, as in the Figure 1.1. This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts t...
NDQ_016821
earths magnetic field is a huge region.
a. true, b. false
a
Lesson: earth as a magnet Earths Magnetic Poles: Imagine a huge bar magnet passing through Earths axis, as in the Figure 1.1. This is a good representation of Earth as a magnet. Like a bar magnet, Earth has north and south magnetic poles. A magnetic pole is the north or south end of a magnet, where the magnet exerts t...
NDQ_016823
all machines make work easier.
a. true, b. false
a
Lesson: efficiency Machines and Friction: A dolly is a machine because it changes a force to make work easier. What is work? In physics, work is defined as the use of force to move an object over a distance. It is represented by the equation: Work = Force x Distance All machines make work easier, but they dont increas...
NDQ_016824
you can get more work out of a machine than you put into it.
a. true, b. false
b
Lesson: efficiency Machines and Friction: A dolly is a machine because it changes a force to make work easier. What is work? In physics, work is defined as the use of force to move an object over a distance. It is represented by the equation: Work = Force x Distance All machines make work easier, but they dont increas...
NDQ_016827
the percent of the work put into a machine (input work) that is actually used to do work (output work) is a measure of the machines
a. power, b. efficiency, c. mechanical advantage, d. none of the above
b
Lesson: efficiency Machines and Friction: A dolly is a machine because it changes a force to make work easier. What is work? In physics, work is defined as the use of force to move an object over a distance. It is represented by the equation: Work = Force x Distance All machines make work easier, but they dont increas...
NDQ_016829
which equation is used to calculate the efficiency of a machine?
a. efficiency = input distance/output distance x 100%, b. efficiency = input force/output force x 100%, c. efficiency = input work/output work x 100%, d. none of the above
d
Lesson: efficiency Machines and Friction: A dolly is a machine because it changes a force to make work easier. What is work? In physics, work is defined as the use of force to move an object over a distance. It is represented by the equation: Work = Force x Distance All machines make work easier, but they dont increas...
NDQ_016833
newtons law of gravity was accepted for more than 200 years.
a. true, b. false
a
Lesson: einsteins concept of gravity It Started with Newton: In the late 1600s, Isaac Newton introduced his law of gravity, which identifies gravity as a force of attraction between all objects with mass in the universe. The law also states that the strength of gravity between two objects depends on their mass and dis...
NDQ_016835
newtons law of gravity explains why gravity occurs.
a. true, b. false
b
Lesson: einsteins concept of gravity It Started with Newton: In the late 1600s, Isaac Newton introduced his law of gravity, which identifies gravity as a force of attraction between all objects with mass in the universe. The law also states that the strength of gravity between two objects depends on their mass and dis...
NDQ_016836
einsteins concept of gravity involves
a. mass, b. space, c. time, d. all of the above
d
Lesson: einsteins concept of gravity It Started with Newton: In the late 1600s, Isaac Newton introduced his law of gravity, which identifies gravity as a force of attraction between all objects with mass in the universe. The law also states that the strength of gravity between two objects depends on their mass and dis...
NDQ_016837
einstein explained gravity with his theory of universal gravitation.
a. true, b. false
b
Lesson: einsteins concept of gravity It Started with Newton: In the late 1600s, Isaac Newton introduced his law of gravity, which identifies gravity as a force of attraction between all objects with mass in the universe. The law also states that the strength of gravity between two objects depends on their mass and dis...
NDQ_016838
einstein developed his theory about gravity by using
a. evidence, b. observations, c. mathematics, d. scientific laws
c
Lesson: einsteins concept of gravity It Started with Newton: In the late 1600s, Isaac Newton introduced his law of gravity, which identifies gravity as a force of attraction between all objects with mass in the universe. The law also states that the strength of gravity between two objects depends on their mass and dis...
NDQ_016840
einsteins concept of gravity is similar to what happens when you place a bowling ball on the surface of a trampoline. in this analogy, if the bowling ball represents earth, then the surface of the trampoline represents
a. space-time, b. earths gravity, c. earths mass, d. none of the above
a
Lesson: einsteins concept of gravity It Started with Newton: In the late 1600s, Isaac Newton introduced his law of gravity, which identifies gravity as a force of attraction between all objects with mass in the universe. The law also states that the strength of gravity between two objects depends on their mass and dis...
NDQ_016844
the less an elastic material is stretched or compressed, the greater the force it exerts.
a. true, b. false
b
Lesson: elastic force Elasticity and Elastic Force: Something that is elastic can return to its original shape after being stretched or compressed. This property is called elasticity. As you stretch or compress an elastic material like a bungee cord, it resists the change in shape. It exerts a counter force in the opp...
NDQ_016845
elastic force causes an elastic material to spring back to its original shape after being stretched or compressed.
a. true, b. false
a
Lesson: elastic force Elasticity and Elastic Force: Something that is elastic can return to its original shape after being stretched or compressed. This property is called elasticity. As you stretch or compress an elastic material like a bungee cord, it resists the change in shape. It exerts a counter force in the opp...
NDQ_016849
play objects with elasticity include
a. spring toys, b. silly putty, c. modeling clay, d. all of the above
a
Lesson: elastic force Elasticity and Elastic Force: Something that is elastic can return to its original shape after being stretched or compressed. This property is called elasticity. As you stretch or compress an elastic material like a bungee cord, it resists the change in shape. It exerts a counter force in the opp...
NDQ_016851
an elastic material offers no resistance to forces that change its shape.
a. true, b. false
b
Lesson: elastic force Elasticity and Elastic Force: Something that is elastic can return to its original shape after being stretched or compressed. This property is called elasticity. As you stretch or compress an elastic material like a bungee cord, it resists the change in shape. It exerts a counter force in the opp...
NDQ_016992
most of the electromagnetic radiation on earth comes from the sun.
a. true, b. false
a
Lesson: electromagnetic spectrum Electromagnetic Radiation: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave freq...
NDQ_016993
electromagnetic waves with longer wavelengths have
a. higher frequencies, b. more energy, c. faster speeds, d. none of the above
d
Lesson: electromagnetic spectrum Electromagnetic Radiation: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave freq...
NDQ_016995
electromagnetic waves with the longest wavelengths are
a. gamma rays, b. x rays, c. infrared light, d. radio waves
d
Lesson: electromagnetic spectrum Electromagnetic Radiation: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave freq...
NDQ_016996
electromagnetic waves with the greatest amount of energy are
a. microwaves, b. ultraviolet light, c. infrared light, d. gamma rays
d
Lesson: electromagnetic spectrum Electromagnetic Radiation: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave freq...
NDQ_016997
the frequencies of electromagnetic waves range from
a. 104 to 1020 waves/second, b. 108 to 1016 waves/second, c. 1010 to 1014 waves/second, d. none of the above
a
Lesson: electromagnetic spectrum Electromagnetic Radiation: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave freq...
NDQ_016998
the only electromagnetic waves in sunlight are ultraviolet, infrared, and visible light.
a. true, b. false
b
Lesson: electromagnetic spectrum Electromagnetic Radiation: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave freq...
NDQ_017000
ultraviolet light has more energy than visible light.
a. true, b. false
a
Lesson: electromagnetic spectrum Electromagnetic Radiation: Electromagnetic radiation is energy that travels in waves across space as well as through matter. Most of the electromagnetic radiation on Earth comes from the sun. Like other waves, electromagnetic waves are characterized by certain wavelengths and wave freq...
NDQ_017002
electromagnetic waves need a medium in order to transfer energy.
a. true, b. false
b
Lesson: electromagnetic waves What Are Electromagnetic Waves: Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. Like other waves, electro- magnetic waves transfer energy from one place to another. The transfer of energy by electromagnetic waves is called electromagnetic radiation....
NDQ_017004
electromagnetic waves
a. create force fields, b. exert force over a distance, c. can travel through outer space, d. all of the above
d
Lesson: electromagnetic waves What Are Electromagnetic Waves: Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. Like other waves, electro- magnetic waves transfer energy from one place to another. The transfer of energy by electromagnetic waves is called electromagnetic radiation....
NDQ_017006
electromagnetic waves are
a. surface waves, b. transverse waves, c. longitudinal waves, d. none of the above
b
Lesson: electromagnetic waves What Are Electromagnetic Waves: Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. Like other waves, electro- magnetic waves transfer energy from one place to another. The transfer of energy by electromagnetic waves is called electromagnetic radiation....
NDQ_017008
when electromagnetic waves strike matter they may be
a. absorbed, b. reflected, c. refracted, d. any of the above
d
Lesson: electromagnetic waves What Are Electromagnetic Waves: Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. Like other waves, electro- magnetic waves transfer energy from one place to another. The transfer of energy by electromagnetic waves is called electromagnetic radiation....
NDQ_017009
electromagnetic waves may be converted to other forms of energy.
a. true, b. false
a
Lesson: electromagnetic waves What Are Electromagnetic Waves: Electromagnetic waves are waves that consist of vibrating electric and magnetic fields. Like other waves, electro- magnetic waves transfer energy from one place to another. The transfer of energy by electromagnetic waves is called electromagnetic radiation....
NDQ_017023
orbitals may be shaped like
a. spheres, b. dumbbells, c. rings, d. all of the above
d
Lesson: electron cloud atomic model Where Are the Electrons: Up until about 1920, scientists accepted Niels Bohrs model of the atom. In this model, negative electrons circle the positive nucleus at fixed distances from the nucleus, called energy levels. You can see the model in Figure 1.1 for an atom of the element ni...
NDQ_017024
the atomic nucleus is always at the center of an orbital.
a. true, b. false
a
Lesson: electron cloud atomic model Where Are the Electrons: Up until about 1920, scientists accepted Niels Bohrs model of the atom. In this model, negative electrons circle the positive nucleus at fixed distances from the nucleus, called energy levels. You can see the model in Figure 1.1 for an atom of the element ni...
NDQ_017026
schroedinger thought that electrons
a. are restricted to very specific orbits, b. might travel in waves like light, c. have very precise locations, d. behave like protons and neutrons
b
Lesson: electron cloud atomic model Where Are the Electrons: Up until about 1920, scientists accepted Niels Bohrs model of the atom. In this model, negative electrons circle the positive nucleus at fixed distances from the nucleus, called energy levels. You can see the model in Figure 1.1 for an atom of the element ni...
NDQ_017027
bohrs atomic model explains all of the behaviors of electrons in atoms of all elements.
a. true, b. false
b
Lesson: electron cloud atomic model Where Are the Electrons: Up until about 1920, scientists accepted Niels Bohrs model of the atom. In this model, negative electrons circle the positive nucleus at fixed distances from the nucleus, called energy levels. You can see the model in Figure 1.1 for an atom of the element ni...
NDQ_017030
the electron cloud model of the atom is no longer accepted by most scientists.
a. true, b. false
b
Lesson: electron cloud atomic model Where Are the Electrons: Up until about 1920, scientists accepted Niels Bohrs model of the atom. In this model, negative electrons circle the positive nucleus at fixed distances from the nucleus, called energy levels. You can see the model in Figure 1.1 for an atom of the element ni...
NDQ_017062
like protons and neutrons, electrons consist of smaller particles.
a. true, b. false
b
Lesson: electrons What Are Electrons: Electrons are one of three main types of particles that make up atoms. The other two types are protons and neutrons. Unlike protons and neutrons, which consist of smaller, simpler particles, electrons are fundamental particles that do not consist of smaller particles. They are a t...
NDQ_017063
an electron has an electrical charge of
a. +1, b. -1, c. 0, d. 0 or -1
b
Lesson: electrons What Are Electrons: Electrons are one of three main types of particles that make up atoms. The other two types are protons and neutrons. Unlike protons and neutrons, which consist of smaller, simpler particles, electrons are fundamental particles that do not consist of smaller particles. They are a t...
NDQ_017064
an electron has about the same mass as a proton.
a. true, b. false
b
Lesson: electrons What Are Electrons: Electrons are one of three main types of particles that make up atoms. The other two types are protons and neutrons. Unlike protons and neutrons, which consist of smaller, simpler particles, electrons are fundamental particles that do not consist of smaller particles. They are a t...
NDQ_017065
atoms always have the same number of electrons as protons.
a. true, b. false
a
Lesson: electrons What Are Electrons: Electrons are one of three main types of particles that make up atoms. The other two types are protons and neutrons. Unlike protons and neutrons, which consist of smaller, simpler particles, electrons are fundamental particles that do not consist of smaller particles. They are a t...
NDQ_017070
what is the maximum number of electrons each orbital can hold?
a. 1, b. 2, c. 4, d. 8
b
Lesson: electrons What Are Electrons: Electrons are one of three main types of particles that make up atoms. The other two types are protons and neutrons. Unlike protons and neutrons, which consist of smaller, simpler particles, electrons are fundamental particles that do not consist of smaller particles. They are a t...
NDQ_017074
no two elements are exactly alike.
a. true, b. false
a
Lesson: elements Pure Substances: A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances. Currently, 92 different elements are known to exist in nature, although additional elements have been formed in labs. All matter consists of one or more of t...
NDQ_017075
which of the following substances is not an element?
a. oxygen, b. water, c. nitrogen, d. hydrogen
b
Lesson: elements Pure Substances: A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances. Currently, 92 different elements are known to exist in nature, although additional elements have been formed in labs. All matter consists of one or more of t...
NDQ_017076
which element is attracted by a magnet?
a. silver, b. aluminum, c. lead, d. iron
d
Lesson: elements Pure Substances: A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances. Currently, 92 different elements are known to exist in nature, although additional elements have been formed in labs. All matter consists of one or more of t...
NDQ_017077
which element glows red when electricity flows through it?
a. iron, b. mercury, c. neon, d. copper
c
Lesson: elements Pure Substances: A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances. Currently, 92 different elements are known to exist in nature, although additional elements have been formed in labs. All matter consists of one or more of t...
NDQ_017078
carbon is the most common element in living things.
a. true, b. false
a
Lesson: elements Pure Substances: A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances. Currently, 92 different elements are known to exist in nature, although additional elements have been formed in labs. All matter consists of one or more of t...
NDQ_017079
aristotle correctly identified four of the elements.
a. true, b. false
b
Lesson: elements Pure Substances: A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances. Currently, 92 different elements are known to exist in nature, although additional elements have been formed in labs. All matter consists of one or more of t...
NDQ_017080
the smallest particle of an element is a(n)
a. molecule, b. crystal, c. compound, d. atom
d
Lesson: elements Pure Substances: A pure substance is called an element. An element is a pure substance because it cannot be separated into any other substances. Currently, 92 different elements are known to exist in nature, although additional elements have been formed in labs. All matter consists of one or more of t...
NDQ_017081
only endothermic chemical reactions involve energy.
a. true, b. false
b
Lesson: endothermic reactions What Is An Endothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called exothermic reactions, more energy is released when new bonds form in the products ...
NDQ_017083
in an endothermic reaction, it takes less energy to break bonds in the reactants than is released when new bonds form in the products.
a. true, b. false
b
Lesson: endothermic reactions What Is An Endothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called exothermic reactions, more energy is released when new bonds form in the products ...
NDQ_017085
a constant input of energy is needed to keep an endothermic reaction going.
a. true, b. false
a
Lesson: endothermic reactions What Is An Endothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called exothermic reactions, more energy is released when new bonds form in the products ...
NDQ_017087
which statement about the chemical reactions of photosynthesis is true?
a. they are endothermic, b. they produce energy in the form of light, c. they can be represented by 6co2 + 6h2o c6h12o6 + 6o2, d. two of the above
d
Lesson: endothermic reactions What Is An Endothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called exothermic reactions, more energy is released when new bonds form in the products ...
NDQ_017088
during an endothermic reaction, energy is
a. absorbed, b. released, c. destroyed, d. created
a
Lesson: endothermic reactions What Is An Endothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called exothermic reactions, more energy is released when new bonds form in the products ...
NDQ_017094
when work is done, energy is transferred from one object to another.
a. true, b. false
a
Lesson: energy Defining Energy: Energy is defined in science as the ability to move matter or change matter in some other way. Energy can also be defined as the ability to do work, which means using force to move an object over a distance. When work is done, energy is transferred from one object to another. For exampl...
NDQ_017095
the si unit for energy is the newton.
a. true, b. false
b
Lesson: energy Defining Energy: Energy is defined in science as the ability to move matter or change matter in some other way. Energy can also be defined as the ability to do work, which means using force to move an object over a distance. When work is done, energy is transferred from one object to another. For exampl...
NDQ_017096
forms of energy include
a. chemical energy, b. mechanical energy, c. thermal energy, d. all of the above
d
Lesson: energy Defining Energy: Energy is defined in science as the ability to move matter or change matter in some other way. Energy can also be defined as the ability to do work, which means using force to move an object over a distance. When work is done, energy is transferred from one object to another. For exampl...
NDQ_017097
anything that is moving has kinetic energy.
a. true, b. false
a
Lesson: energy Defining Energy: Energy is defined in science as the ability to move matter or change matter in some other way. Energy can also be defined as the ability to do work, which means using force to move an object over a distance. When work is done, energy is transferred from one object to another. For exampl...
NDQ_017099
when you run around a track, which type of energy are you demonstrating?
a. mechanical energy, b. potential energy, c. kinetic energy, d. two of the above
d
Lesson: energy Defining Energy: Energy is defined in science as the ability to move matter or change matter in some other way. Energy can also be defined as the ability to do work, which means using force to move an object over a distance. When work is done, energy is transferred from one object to another. For exampl...
NDQ_017101
energy conversion means saving energy.
a. true, b. false
b
Lesson: energy conversion Defining Gravity: Gravity is a force, but not like other forces you may know. Gravity is a bit special. You know that a force is a push or pull. If you push a ball, it starts to roll. If you lift a book, it moves upward. Now, imagine you drop a ball. It falls to the ground. Can you see the fo...
NDQ_017105
most electricity comes from the burning of
a. fossil fuels, b. trash, c. wood, d. none of the above
a
Lesson: energy conversion Defining Gravity: Gravity is a force, but not like other forces you may know. Gravity is a bit special. You know that a force is a push or pull. If you push a ball, it starts to roll. If you lift a book, it moves upward. Now, imagine you drop a ball. It falls to the ground. Can you see the fo...
NDQ_017106
any form of energy can change into any other form of energy.
a. true, b. false
a
Lesson: energy conversion Defining Gravity: Gravity is a force, but not like other forces you may know. Gravity is a bit special. You know that a force is a push or pull. If you push a ball, it starts to roll. If you lift a book, it moves upward. Now, imagine you drop a ball. It falls to the ground. Can you see the fo...
NDQ_017107
one form of energy can change into two or more other forms of energy.
a. true, b. false
a
Lesson: energy conversion Defining Gravity: Gravity is a force, but not like other forces you may know. Gravity is a bit special. You know that a force is a push or pull. If you push a ball, it starts to roll. If you lift a book, it moves upward. Now, imagine you drop a ball. It falls to the ground. Can you see the fo...
NDQ_017109
examples of the energy conversion described in question 8 include
a. using a playground slide, b. going up and down stairs, c. bouncing on a trampoline, d. all of the above
d
Lesson: energy conversion Defining Gravity: Gravity is a force, but not like other forces you may know. Gravity is a bit special. You know that a force is a push or pull. If you push a ball, it starts to roll. If you lift a book, it moves upward. Now, imagine you drop a ball. It falls to the ground. Can you see the fo...
NDQ_017112
electrons can occupy the spaces between energy levels.
a. true, b. false
b
Lesson: energy level What Are Energy Levels: Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the ste...
NDQ_017113
electrons in the first energy level have the least amount of energy.
a. true, b. false
a
Lesson: energy level What Are Energy Levels: Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the ste...
NDQ_017115
if an atom has just three electrons, they will be located in energy level(s)
a. i and ii, b. i, ii, and iii, c. i only, d. i or ii
a
Lesson: energy level What Are Energy Levels: Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the ste...
NDQ_017117
how many electrons can each orbital hold?
a. 1, b. 2, c. 3, d. 4
b
Lesson: energy level What Are Energy Levels: Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the ste...
NDQ_017119
any atom is most stable when its outermost energy level contains
a. a maximum of two electrons, b. a total of eight electrons, c. as many electrons as it can hold, d. fewer electrons than it can hold
c
Lesson: energy level What Are Energy Levels: Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the ste...
NDQ_017120
valence electrons determine how reactive an element is.
a. true, b. false
a
Lesson: energy level What Are Energy Levels: Energy levels (also called electron shells) are fixed distances from the nucleus of an atom where electrons may be found. Electrons are tiny, negatively charged particles in an atom that move around the positive nucleus at the center. Energy levels are a little like the ste...
NDQ_017123
enzymes work by providing activation energy.
a. true, b. false
b
Lesson: enzymes as catalysts Why Living Things Need Enzymes: Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. Thats where enzymes come in. Enzymes are catalysts in living things. Like o...
NDQ_017124
enzymes are used up in the reactions they catalyze.
a. true, b. false
b
Lesson: enzymes as catalysts Why Living Things Need Enzymes: Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. Thats where enzymes come in. Enzymes are catalysts in living things. Like o...
NDQ_017126
a human enzyme that helps digest starch is
a. pepsase, b. starchase, c. amylase, d. glucase
c
Lesson: enzymes as catalysts Why Living Things Need Enzymes: Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. Thats where enzymes come in. Enzymes are catalysts in living things. Like o...
NDQ_017127
which of the following statements about enzymes if false?
a. enzymes are highly specialized for the reactions they catalyze, b. enzymes are very effective at speeding up reactions, c. enzymes are very efficient at catalyzing reactions, d. enzymes usually result in the formation of waste products
d
Lesson: enzymes as catalysts Why Living Things Need Enzymes: Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. Thats where enzymes come in. Enzymes are catalysts in living things. Like o...
NDQ_017129
about 100 different enzymes are needed for human life.
a. true, b. false
b
Lesson: enzymes as catalysts Why Living Things Need Enzymes: Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. Thats where enzymes come in. Enzymes are catalysts in living things. Like o...
NDQ_017130
enzymes are
a. proteins, b. encoded in dna, c. made in the cells where they are needed, d. all of the above
d
Lesson: enzymes as catalysts Why Living Things Need Enzymes: Chemical reactions constantly occur inside the cells of living things. However, under the conditions inside cells, most biochemical reactions would occur too slowly to maintain life. Thats where enzymes come in. Enzymes are catalysts in living things. Like o...
NDQ_017153
in an exothermic reaction, the reactants have more stored chemical energy than the products.
a. true, b. false
a
Lesson: exothermic reactions What Is An Exothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called endothermic reactions, less energy is released when new bonds form in the products t...
NDQ_017154
in an exothermic reaction, it takes more energy to break bonds in the reactants than is released when new bonds form in the products.
a. true, b. false
b
Lesson: exothermic reactions What Is An Exothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called endothermic reactions, less energy is released when new bonds form in the products t...
NDQ_017156
all combustion reactions are exothermic reactions.
a. true, b. false
a
Lesson: exothermic reactions What Is An Exothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called endothermic reactions, less energy is released when new bonds form in the products t...
NDQ_017158
which of the following reactions is exothermic?
a. ch4 + f2 ch3f + hf, b. ch4 + 2o2 co2 + 2h2o, c. 2h2o 2h2 + o2, d. two of the above
d
Lesson: exothermic reactions What Is An Exothermic Reaction: All chemical reactions involve energy. Energy is used to break bonds in reactants, and energy is released when new bonds form in products. In some chemical reactions, called endothermic reactions, less energy is released when new bonds form in the products t...
NDQ_017163
a steam engine is an external combustion engine.
a. true, b. false
a
Lesson: external combustion engines What Is a Combustion Engine: A combustion engine is a complex machine that burns fuel to produce thermal energy and then uses the thermal energy to do work. There are two types of combustion engines: external and internal. A steam engine is an external combustion engine. How Exter...
NDQ_017165
an external combustion engine
a. burns fuel outside the engine, b. changes kinetic energy to thermal energy, c. runs on electricity, d. all of the above
a
Lesson: external combustion engines What Is a Combustion Engine: A combustion engine is a complex machine that burns fuel to produce thermal energy and then uses the thermal energy to do work. There are two types of combustion engines: external and internal. A steam engine is an external combustion engine. How Exter...
NDQ_017167
the kinetic energy of an external combustion engine can be used to
a. turn the wheels of a vehicle, b. turn a turbine, c. run other machines, d. all of the above
d
Lesson: external combustion engines What Is a Combustion Engine: A combustion engine is a complex machine that burns fuel to produce thermal energy and then uses the thermal energy to do work. There are two types of combustion engines: external and internal. A steam engine is an external combustion engine. How Exter...