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The magnetosphere | (A) completely surrounds Earth (B) is found only near Earths poles (C) exists over a region larger than Earth (D) two of the above | D | Like all magnets, Earth has a magnetic field. Earths magnetic field is called the magnetosphere. It is a huge region that extends outward from Earth for several thousand kilometers but is strongest at the poles. You can see the extent of the magnetosphere in Figure 24.12. For an animated version of the magnetosphere, w... |
Earths magnetic field occurs only over the north and south poles. | (A) true (B) false | B | Like a bar magnet, planet Earth has north and south magnetic poles and a magnetic field over which it exerts magnetic force. Earths magnetic field is called the magnetosphere. You can see it in the Figure 1.1. |
Earths magnetic force is exerted over a distance. | (A) true (B) false | A | Like all magnets, Earth has a magnetic field. Earths magnetic field is called the magnetosphere. You can see a model of the magnetosphere in the Figure 1.3. It is a huge region that extends outward from Earth in all directions. Earth exerts magnetic force over the entire field, but the force is strongest at the poles, ... |
Which statement about magnetic reversals is false? | (A) Magnetic reversals have occurred hundreds of times (B) The most recent magnetic reversal occurred 330 million years ago (C) There is hard evidence showing that magnetic reversals have occurred (D) Scientists do not know for certain why magnetic reversals have occurred | B | Scientists dont know for certain why magnetic reversals occur, but there is hard evidence that they have for hundreds of millions of years. The evidence comes from rocks on the ocean floor. Look at Figure 1.2. They show the same ridge on the ocean floor during different periods of time. A. At the center of the ridge, h... |
The idea that Earth is a magnet was first proposed | (A) by William Gilbert in 1800 (B) after seismographs were developed (C) before scientists learned about Earths inner structure (D) around the same time that Earths outer core was discovered | C | The idea that Earth is a magnet is far from new. It was first proposed in 1600 by a British physician named William Gilbert. However, explaining why Earth acts like a magnet is a relatively recent discovery. It had to wait until the development of technologies such as seismographs, which detect and measure earthquake w... |
Many migrating birds | (A) navigate using Earths magnetic field (B) may be able to see Earths magnetic field (C) have natural compasses that they use for migration (D) all of the above | D | There are about 10,000 living species of birds. Almost all of them can fly. Very few birds are flightless. |
about 80 north latitude | (A) magnetosphere (B) north geographic pole (C) outer core (D) north magnetic pole (E) magnetic reversal (F) compass (G) inner core | D | A look on a reliable website shows us that Old Faithful Geyser is located at N44o 27 43. What does this mean? Latitude tells the distance north or south of the Equator. Latitude lines start at the Equator and circle around the planet. The North Pole is 90o N, with 90 degree lines in the Northern Hemisphere. Old Faithfu... |
solid sphere that makes up Earths center | (A) magnetosphere (B) north geographic pole (C) outer core (D) north magnetic pole (E) magnetic reversal (F) compass (G) inner core | G | The dense, iron core forms the center of the Earth. Scientists know that the core is metal from studying metallic meteorites and the Earths density. Seismic waves show that the outer core is liquid, while the inner core is solid. Movement within Earths outer liquid iron core creates Earths magnetic field. These convect... |
exactly 90 north latitude | (A) magnetosphere (B) north geographic pole (C) outer core (D) north magnetic pole (E) magnetic reversal (F) compass (G) inner core | B | A look on a reliable website shows us that Old Faithful Geyser is located at N44o 27 43. What does this mean? Latitude tells the distance north or south of the Equator. Latitude lines start at the Equator and circle around the planet. The North Pole is 90o N, with 90 degree lines in the Northern Hemisphere. Old Faithfu... |
region deep inside Earth that consists of liquid metals | (A) magnetosphere (B) north geographic pole (C) outer core (D) north magnetic pole (E) magnetic reversal (F) compass (G) inner core | C | The dense, iron core forms the center of the Earth. Scientists know that the core is metal from studying metallic meteorites and the Earths density. Seismic waves show that the outer core is liquid, while the inner core is solid. Movement within Earths outer liquid iron core creates Earths magnetic field. These convect... |
Earths magnetic field | (A) magnetosphere (B) north geographic pole (C) outer core (D) north magnetic pole (E) magnetic reversal (F) compass (G) inner core | A | Earth has a magnetic field (Figure 24.6). The magnetic field has north and south poles. The field extends several thousand kilometers into space. Earths magnetic field is created by the movements of molten metal in the outer core. Earths magnetic field shields us from harmful radiation from the Sun (Figure 24.7). If yo... |
switching of Earths north and south magnetic poles | (A) magnetosphere (B) north geographic pole (C) outer core (D) north magnetic pole (E) magnetic reversal (F) compass (G) inner core | E | Indeed, scientists discovered something astonishing. Many times in Earths history, the magnetic poles have switched positions. North becomes south and south becomes north! When the north and south poles are aligned as they are now, geologists say it is normal polarity. When they are in the opposite position, they say t... |
navigation device that always points north | (A) magnetosphere (B) north geographic pole (C) outer core (D) north magnetic pole (E) magnetic reversal (F) compass (G) inner core | F | When an object is moving, it is not enough to describe its location. We also need to know direction. Direction is important for describing moving objects. For example, a wind blows a storm over your school. Where is that storm coming from? Where is it going? The most common way to describe direction is by using a compa... |
homogeneous mixture in which particles are too small to be seen | (A) colloid (B) compound (C) element (D) mixture (E) solution (F) suspension (G) crystal | E | Mixtures have different properties depending on the size of their particles. Three types of mixtures based on particle size are solutions, suspensions, and colloids, all of which are described in Table 1.1. Click image to the left or use the URL below. URL: Click image to the left or use the URL below. URL: Type of M... |
The most common element in Earths crust is | (A) water (B) iron (C) hydrogen (D) oxygen | D | An element is a pure substance. It cannot be separated into any other substances. There are more than 90 different elements that occur in nature. Some are much more common than others. Hydrogen is the most common element in the universe. Oxygen is the most common element in Earths crust. Figure 3.7 shows other examples... |
combination of two or more substances in any proportions | (A) colloid (B) compound (C) element (D) mixture (E) solution (F) suspension (G) crystal | D | Not all combined substances are compounds. Some are mixtures. A mixture is a combination of two or more substances in any proportion. The substances in a mixture may be elements or compounds. The substances dont combine chemically to form a new substance, as they do in a compound. Instead, they keep their original prop... |
The smallest particle of an element that still has the elements properties is a(n) | (A) crystal (B) compound (C) atom (D) molecule | C | The smallest particle of an element that still has the elements properties is an atom. All the atoms of an element are alike, and they are different from the atoms of all other elements. For example, atoms of gold are the same whether they are found in a gold nugget or a gold ring (see Figure 3.8). All gold atoms have ... |
homogeneous mixture in which particles are big enough to reflect light | (A) colloid (B) compound (C) element (D) mixture (E) solution (F) suspension (G) crystal | A | Mixtures have different properties depending on the size of their particles. Three types of mixtures based on particle size are described below. Figure 3.13 shows examples of each type. You can watch videos about the three types of mixtures at these links: MEDIA Click image to the left or use the URL below. URL: MEDIA... |
Aristotle thought there were four elements, including | (A) air (B) earth (C) water (D) all of the above | D | For thousands of years, people have wondered about the substances that make up matter. About 2500 years ago, the Greek philosopher Aristotle argued that all matter is made up of just four elements, which he identified as earth, air, water, and fire. He thought that different substances vary in their properties because ... |
Whenever elements combine physically, they form | (A) mixtures (B) solutions (C) compounds (D) suspensions | A | There are millions of different substances in the world. Thats because elements can combine in many different ways to form new substances. In fact, most elements are found in compounds. A compound is a unique substance that forms when two or more elements combine chemically. An example is water, which forms when hydrog... |
heterogeneous mixture | (A) colloid (B) compound (C) element (D) mixture (E) solution (F) suspension (G) crystal | F | The lemonade in the opening picture is an example of a homogeneous mixture. A homogeneous mixture has the same composition throughout. Another example of a homogeneous mixture is salt water. If you analyzed samples of ocean water in different places, you would find that the proportion of salt in each sample is the same... |
unique substance that forms when two or more elements combine chemically | (A) colloid (B) compound (C) element (D) mixture (E) solution (F) suspension (G) crystal | B | There are millions of different substances in the world. Thats because elements can combine in many different ways to form new substances. In fact, most elements are found in compounds. A compound is a unique substance that forms when two or more elements combine chemically. An example is water, which forms when hydrog... |
Which of the following is the best example of a heterogeneous mixture? | (A) raisin bran (B) milk (C) orange juice (D) water | A | The lemonade in the opening picture is an example of a homogeneous mixture. A homogeneous mixture has the same composition throughout. Another example of a homogeneous mixture is salt water. If you analyzed samples of ocean water in different places, you would find that the proportion of salt in each sample is the same... |
rigid, lattice-like framework of many ions bonded together | (A) colloid (B) compound (C) element (D) mixture (E) solution (F) suspension (G) crystal | G | Compounds like sodium chloride form structures called crystals. A crystal is a rigid framework of many ions locked together in a repeating pattern. Ions are electrically charged forms of atoms. You can see a crystal of sodium chloride in the Figure 1.3. It is made up of many sodium and chloride ions. Sodium and chlorin... |
pure substance that cannot be separated into any other substances | (A) colloid (B) compound (C) element (D) mixture (E) solution (F) suspension (G) crystal | C | 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 these elements. Some elements are ve... |
I am lighter than air and used to fill balloons. Which element am I? | (A) neon (B) carbon (C) oxygen (D) helium | D | Did you ever get a birthday balloon like the one pictured 1.2? The balloon is filled with the noble gas helium. The gas is pumped from a tank into a Mylar balloon. Unlike a balloon filled with air, a balloon filled with helium needs to be weighted down so it wont float away. Q: Why does a helium balloon float away if i... |
Iron and nickel are both | (A) elements (B) metals (C) compounds (D) two of the above | D | Each element has a unique set of properties that make it different from all other elements. As a result, elements can be identified by their properties. For example, the elements iron and nickel are both metals that are good conductors of heat and electricity. However, iron is attracted by a magnet, whereas nickel is n... |
Which statement is false about the atoms of a given element? | (A) They are all alike (B) They are the same as the atoms of all other elements (C) They have properties of the given element (D) They all have the same structure | B | The number of protons per atom is always the same for a given element. However, the number of neutrons may vary, and the number of electrons can change. |
Atoms of the same element are all alike. | (A) true (B) false | A | The smallest particle of an element that still has the elements properties is an atom. All the atoms of an element are alike, and they are different from the atoms of all other elements. For example, atoms of gold are the same whether they are found in a gold nugget or a gold ring (see Figure 3.8). All gold atoms have ... |
John Dalton made all the following contributions to our knowledge of atoms except | (A) doing research to show atoms exist (B) introducing modern ideas about atoms (C) developing a theory of the atom (D) arguing that atoms do not exist | D | From his research, Dalton developed a theory about atoms. Daltons atomic theory consists of three basic ideas: All substances are made of atoms. Atoms are the smallest particles of matter. They cannot be divided into smaller particles, created, or destroyed. All atoms of the same element are alike and have the same mas... |
Each compound has a unique set of properties. | (A) true (B) false | A | There are millions of different substances in the world. Thats because elements can combine in many different ways to form new substances. In fact, most elements are found in compounds. A compound is a unique substance that forms when two or more elements combine chemically. An example is water, which forms when hydrog... |
Which drink is an example of a compound? | (A) lemonade (B) ice tea (C) vanilla milkshake (D) water | D | There are millions of different substances in the world. Thats because elements can combine in many different ways to form new substances. In fact, most elements are found in compounds. A compound is a unique substance that forms when two or more elements combine chemically. An example is water, which forms when hydrog... |
An example of a heterogeneous mixture is | (A) salt water (B) gelatin (C) milk (D) trail mix | D | The lemonade in the opening picture is an example of a homogeneous mixture. A homogeneous mixture has the same composition throughout. Another example of a homogeneous mixture is salt water. If you analyzed samples of ocean water in different places, you would find that the proportion of salt in each sample is the same... |
Atoms can be seen with a hand lens. | (A) true (B) false | B | Unlike LEGO bricks, atoms are extremely small. The radius of an atom is well under 1 nanometer. Thats one- billionth of a meter. Such a number is hard to imagine. Consider this: trillions of atoms would fit inside the period at the end of this sentence. In other words, atoms are way too small to be seen with the naked ... |
Which mixture has the largest particles? | (A) muddy water (B) salt water (C) milk (D) lemonade | A | Mixtures have different properties depending on the size of their particles. Three types of mixtures based on particle size are solutions, suspensions, and colloids, all of which are described in Table 1.1. Click image to the left or use the URL below. URL: Click image to the left or use the URL below. URL: Type of M... |
There are millions of different elements in the universe. | (A) true (B) false | B | All known matter can be divided into a little more than 100 different substances called elements. |
A crystal consists of molecules that are bonded together. | (A) true (B) false | B | The smallest particle of a compound that still has the compounds properties is a molecule. A molecule consists of two or more atoms that are joined together. For example, a molecule of water consists of two hydrogen atoms joined to one oxygen atom (see Figure 3.10). You can learn more about molecules at this link: Som... |
Each element has a unique set of properties. | (A) true (B) false | A | Each element has a unique set of properties that make it different from all other elements. As a result, elements can be identified by their properties. For example, the elements iron and nickel are both metals that are good conductors of heat and electricity. However, iron is attracted by a magnet, whereas nickel is n... |
The idea of elements was first introduced by John Dalton. | (A) true (B) false | B | Around 1800, a British chemist named John Dalton revived Democrituss early ideas about the atom. Dalton is pictured in Figure 5.8. He made a living by teaching and just did research in his spare time. Nonetheless, from his research results, he developed one of the most important theories in science. |
Most elements are found in compounds. | (A) true (B) false | A | There are millions of different substances in the world. Thats because elements can combine in many different ways to form new substances. In fact, most elements are found in compounds. A compound is a unique substance that forms when two or more elements combine chemically. An example is water, which forms when hydrog... |
A compound has the same properties as the substances it contains. | (A) true (B) false | B | There are millions of different substances in the world. Thats because elements can combine in many different ways to form new substances. In fact, most elements are found in compounds. A compound is a unique substance that forms when two or more elements combine chemically. An example is water, which forms when hydrog... |
A molecule consists of two or more atoms. | (A) true (B) false | A | A molecule is the smallest unit of a chemical compound. A compound is a substance made of two or more elements. The elements in a chemical compound are always present in a certain ratio. Water is probably one of the simplest compounds that you know. A water molecule is made of two hydrogen atoms and one oxygen atom (Fi... |
Table salt is an example of a compound that forms molecules. | (A) true (B) false | B | The smallest particle of a compound that still has the compounds properties is a molecule. A molecule consists of two or more atoms that are joined together. For example, a molecule of water consists of two hydrogen atoms joined to one oxygen atom (see Figure 3.10). You can learn more about molecules at this link: Som... |
The substances in a mixture may be elements or compounds. | (A) true (B) false | A | Not all combined substances are compounds. Some are mixtures. A mixture is a combination of two or more substances in any proportion. The substances in a mixture may be elements or compounds. The substances dont combine chemically to form a new substance, as they do in a compound. Instead, they keep their original prop... |
A package of mixed seeds is a homogeneous mixture. | (A) true (B) false | B | Some mixtures are homogeneous. This means they have the same composition throughout. An example is salt water in the ocean. Ocean water everywhere is about 3.5 percent salt. Some mixtures are heterogeneous. This means they vary in their composition. An example is trail mix. No two samples of trail mix, even from the sa... |
Mixtures are classified on the basis of particle size. | (A) true (B) false | A | Mixtures have different properties depending on the size of their particles. Three types of mixtures based on particle size are solutions, suspensions, and colloids, all of which are described in Table 1.1. Click image to the left or use the URL below. URL: Click image to the left or use the URL below. URL: Type of M... |
Components of mixtures rarely can be separated. | (A) true (B) false | B | Not all combined substances are compounds. Some are mixtures. A mixture is a combination of two or more substances in any proportion. The substances in a mixture may be elements or compounds. The substances dont combine chemically to form a new substance, as they do in a compound. Instead, they keep their original prop... |
electrically neutral atomic particle inside the nucleus of an atom | (A) electron (B) ion (C) isotope (D) neutron (E) nucleus (F) proton (G) quark | D | A neutron is a particle inside the nucleus of an atom. It has no electric charge. Atoms of an element often have the same number of neutrons as protons. For example, most carbon atoms have six neutrons as well as six protons. This is also shown in Figure below . |
The smallest particles of an element that still have the elements properties are | (A) quarks (B) gluons (C) protons (D) atoms | D | The smallest particle of an element that still has the elements properties is an atom. All the atoms of an element are alike, and they are different from the atoms of all other elements. For example, atoms of gold are the same whether they are found in a gold nugget or a gold ring (see Figure 3.8). All gold atoms have ... |
atom that differs in its number of neutrons from other atoms of the same element | (A) electron (B) ion (C) isotope (D) neutron (E) nucleus (F) proton (G) quark | C | All atoms of the same element have the same number of protons, but some may have different numbers of neutrons. For example, all carbon atoms have six protons, and most have six neutrons as well. But some carbon atoms have seven or eight neutrons instead of the usual six. Atoms of the same element that differ in their ... |
Which statement is true about the nucleus of an atom? | (A) It makes up most of the atoms volume (B) It makes up most of the atoms mass (C) It contains protons and electrons (D) It is neutral in electric charge | B | The nucleus (plural, nuclei) is a positively charged region at the center of the atom. It consists of two types of subatomic particles packed tightly together. The particles are protons, which have a positive electric charge, and neutrons, which are neutral in electric charge. Outside of the nucleus, an atom is mostly ... |
negatively charged atomic particle that moves around the nucleus of an atom | (A) electron (B) ion (C) isotope (D) neutron (E) nucleus (F) proton (G) quark | A | Unlike protons and neutrons, which are located inside the nucleus at the center of the atom, electrons are found outside the nucleus. Because opposite electric charges attract each other, negative electrons are attracted to the positive nucleus. This force of attraction keeps electrons constantly moving through the oth... |
The strong force explains why | (A) electrons are attracted to the nucleus (B) the nucleus does not fly apart (C) electrons are smaller than protons (D) none of the above | B | The strong nuclear force is a force of attraction between fundamental particles called quarks, which have a type of charge called color charge. The strong nuclear force is transferred between quarks by fundamental force-carrying particles called gluons. Both protons and neutrons consist of quarks. The exchange of gluon... |
The mass number of an atom is its number of | (A) electrons (B) protons (C) neutrons (D) protons plus neutrons | D | Electrons have almost no mass. Instead, almost all the mass of an atom is in its protons and neutrons in the nucleus. The nucleus is very small, but it is densely packed with matter. The SI unit for the mass of an atom is the atomic mass unit (amu). One atomic mass unit equals the mass of a proton, which is about 1.7 ... |
positively charged atomic particle inside the nucleus of an atom | (A) electron (B) ion (C) isotope (D) neutron (E) nucleus (F) proton (G) quark | F | The nucleus (plural, nuclei) is a positively charged region at the center of the atom. It consists of two types of subatomic particles packed tightly together. The particles are protons, which have a positive electric charge, and neutrons, which are neutral in electric charge. Outside of the nucleus, an atom is mostly ... |
type of particle that makes up protons and neutrons | (A) electron (B) ion (C) isotope (D) neutron (E) nucleus (F) proton (G) quark | G | A neutron is one of three main particles that make up the atom. The other two particles are the proton and electron. Atoms of all elementsexcept for most atoms of hydrogenhave neutrons in their nucleus. The nucleus is the small, dense region at the center of an atom where protons are also found. Atoms generally have ab... |
When a fluorine atom gains an electron, it becomes a(n) | (A) positive ion (B) isotope (C) cation (D) anion | D | Atoms cannot only gain extra electrons. They can also lose electrons. In either case, they become ions. Ions are atoms that have a positive or negative charge because they have unequal numbers of protons and electrons. If atoms lose electrons, they become positive ions, or cations. If atoms gain electrons, they become ... |
charged particle that forms when atom gains or loses electron(s) | (A) electron (B) ion (C) isotope (D) neutron (E) nucleus (F) proton (G) quark | B | The girl pictured above became negatively charged because electrons flowed from the van de Graaff generator to her. Whenever electrons are transferred between objects, neutral matter becomes charged. This occurs even with individual atoms. Atoms are neutral in electric charge because they have the same number of negati... |
tiny region at the center of an atom that contains protons and neutrons | (A) electron (B) ion (C) isotope (D) neutron (E) nucleus (F) proton (G) quark | E | The nucleus (plural, nuclei) is a positively charged region at the center of the atom. It consists of two types of subatomic particles packed tightly together. The particles are protons, which have a positive electric charge, and neutrons, which are neutral in electric charge. Outside of the nucleus, an atom is mostly ... |
All protons are exactly the same. | (A) true (B) false | A | All protons are identical. For example, hydrogen protons are exactly the same as protons of helium and all other elements, or pure substances. However, atoms of different elements have different numbers of protons. In fact, atoms of any given element have a unique number of protons that is different from the numbers of... |
Electrons have the same mass as protons. | (A) true (B) false | B | Electrons are extremely small. The mass of an electron is only about 1/2000 the mass of a proton or neutron, so electrons contribute virtually nothing to the total mass of an atom. Electrons have an electric charge of -1, which is equal but opposite to the charge of proton, which is +1. All atoms have the same number o... |
Atoms may be positive or negative in charge. | (A) true (B) false | B | Atoms are neutral in electric charge because they have the same number of electrons as protons. However, atoms may transfer electrons and become charged ions, as illustrated in Figure 23.5. Positively charged ions, or cations, form when atoms give up electrons. Negatively charged ions, or anions, form when atoms gain e... |
All atoms of a given element have the same number of electrons. | (A) true (B) false | A | The number of protons per atom is always the same for a given element. However, the number of neutrons may vary, and the number of electrons can change. |
There are three quarks in each neutron. | (A) true (B) false | A | Remember the quarks from the first page of this chapter? Quarks are even tinier particles of matter that make up protons and neutrons. There are three quarks in each proton and three quarks in each neutron. The charges of quarks are balanced exactly right to give a positive charge to a proton and a neutral charge to a ... |
Atoms are the smallest particles of matter. | (A) true (B) false | B | The smallest particle of an element that still has the elements properties is an atom. All the atoms of an element are alike, and they are different from the atoms of all other elements. For example, atoms of gold are the same whether they are found in a gold nugget or a gold ring (see Figure 3.8). All gold atoms have ... |
An atom always has the same number of electrons as neutrons. | (A) true (B) false | B | The number of protons per atom is always the same for a given element. However, the number of neutrons may vary, and the number of electrons can change. |
The nucleus is at the center of the atom. | (A) true (B) false | A | The nucleus (plural, nuclei) is a positively charged region at the center of the atom. It consists of two types of subatomic particles packed tightly together. The particles are protons, which have a positive electric charge, and neutrons, which are neutral in electric charge. Outside of the nucleus, an atom is mostly ... |
Atoms have no electric charge. | (A) true (B) false | A | Electrons are extremely small. The mass of an electron is only about 1/2000 the mass of a proton or neutron, so electrons contribute virtually nothing to the total mass of an atom. Electrons have an electric charge of -1, which is equal but opposite to the charge of proton, which is +1. All atoms have the same number o... |
The strong force keeps electrons moving around the nucleus. | (A) true (B) false | B | When it comes to atomic particles, opposites attract. Negative electrons are attracted to positive protons. This force of attraction keeps the electrons moving about the nucleus. An analogy is the way planets orbit the sun. What about particles with the same charge, such as protons in the nucleus? They push apart, or r... |
Electrons have almost no mass. | (A) true (B) false | A | Electrons are extremely small. The mass of an electron is only about 1/2000 the mass of a proton or neutron, so electrons contribute virtually nothing to the total mass of an atom. Electrons have an electric charge of -1, which is equal but opposite to the charge of proton, which is +1. All atoms have the same number o... |
The mass of an atom equals the sum of its protons and neutrons. | (A) true (B) false | A | Electrons have almost no mass. Instead, almost all the mass of an atom is in its protons and neutrons in the nucleus. The nucleus is very small, but it is densely packed with matter. The SI unit for the mass of an atom is the atomic mass unit (amu). One atomic mass unit equals the mass of a proton, which is about 1.7 ... |
For most elements, isotopes are named for their atomic number. | (A) true (B) false | B | For most elements other than hydrogen, isotopes are named for their mass number. For example, carbon atoms with the usual 6 neutrons have a mass number of 12 (6 protons + 6 neutrons = 12), so they are called carbon-12. Carbon atoms with 7 neutrons have an atomic mass of 13 (6 protons + 7 neutrons = 13). These atoms are... |
Each proton consists of three quarks. | (A) true (B) false | A | Remember the quarks from the first page of this chapter? Quarks are even tinier particles of matter that make up protons and neutrons. There are three quarks in each proton and three quarks in each neutron. The charges of quarks are balanced exactly right to give a positive charge to a proton and a neutral charge to a ... |
Quarks are held together by gluons. | (A) true (B) false | A | Gluons make quarks attract each other more strongly the farther apart the quarks get. To understand how gluons work, imagine holding a rubber band between your fingers. If you try to move your hands apart, they will be pulled back together by the rubber band. The farther apart you move your hands, the stronger the forc... |
If an atom were the size of a football stadium, the nucleus would be about the size of a | (A) microwave oven (B) basketball (C) pea (D) car | C | The nucleus of the atom is extremely small. Its radius is only about 1/100,000 of the total radius of the atom. If an atom were the size of a football stadium, the nucleus would be about the size of a pea! Click image to the left or use the URL below. URL: Electrons have virtually no mass, but protons and neutrons hav... |
The number of protons in atoms is | (A) the same for all atoms (B) unique for each element (C) always equal to the number of neutrons (D) none of the above | B | The number of protons per atom is always the same for a given element. However, the number of neutrons may vary, and the number of electrons can change. |
The strong force | (A) affects only nearby particles (B) is stronger than electric force (C) is not effective if the nucleus is too big (D) all of the above | D | The strong nuclear force is a force of attraction between fundamental particles called quarks, which have a type of charge called color charge. The strong nuclear force is transferred between quarks by fundamental force-carrying particles called gluons. Both protons and neutrons consist of quarks. The exchange of gluon... |
A neutron has the same mass as a(n) | (A) nucleus (B) electron (C) proton (D) quark | C | Unlike protons and electrons, which are electrically charged, neutrons have no charge. In other words, they are electrically neutral. Thats why the neutrons in the diagram above are labeled n0 . The zero stands for zero charge. The mass of a neutron is slightly greater than the mass of a proton, which is 1 atomic mass ... |
A nitrogen atom has an atomic number of 7 and a mass number of 14. How many protons, neutrons, and electrons does it have? | (A) 7 protons (B) 14 neutrons (C) 7 electrons (D) b 14 protons (E) 7 neutrons (F) 7 electrons (G) c 7 protons (H) 7 neutrons (I) 7 electrons (J) d 7 protons (K) 7 neutrons (L) 14 electrons | C | Electrons have almost no mass. Instead, almost all the mass of an atom is in its protons and neutrons in the nucleus. The nucleus is very small, but it is densely packed with matter. The SI unit for the mass of an atom is the atomic mass unit (amu). One atomic mass unit equals the mass of a proton, which is about 1.7 ... |
If an atom loses electrons, it becomes a(n) | (A) isotope (B) cation (C) anion (D) gluon | B | Atoms cannot only gain extra electrons. They can also lose electrons. In either case, they become ions. Ions are atoms that have a positive or negative charge because they have unequal numbers of protons and electrons. If atoms lose electrons, they become positive ions, or cations. If atoms gain electrons, they become ... |
How many neutrons are there in the most common isotope of hydrogen? | (A) zero (B) one (C) two (D) three | A | Hydrogen is an example of an element that has isotopes. Three isotopes of hydrogen are modeled in the Figure hydrogen. Some hydrogen atoms have one neutron as well. These atoms are the isotope named deuterium. Other hydrogen atoms have two neutrons. These atoms are the isotope named tritium. Q: The mass number of an at... |
Which statement is not part of the original atomic theory? | (A) Atoms consist of smaller particles of matter (B) Atoms cannot be created or destroyed (C) All atoms of the same element have the same mass (D) Atoms join together to form compounds | A | The atomic theory Dalton developed consists of three ideas: All substances are made of atoms. Atoms are the smallest particles of matter. They cannot be divided into smaller particles. They also cannot be created or destroyed. All atoms of the same element are alike and have the same mass. Atoms of different elements a... |
John Dalton thought that an atom is like a(n) | (A) plum pudding (B) solar system (C) hard solid ball (D) vacuum tube | C | From his research, Dalton developed a theory about atoms. Daltons atomic theory consists of three basic ideas: All substances are made of atoms. Atoms are the smallest particles of matter. They cannot be divided into smaller particles, created, or destroyed. All atoms of the same element are alike and have the same mas... |
The scientist who discovered protons was | (A) John Dalton (B) J (C) Ernest Rutherford (D) James Chadwick | C | Based on his results, Rutherford concluded that all the positive charge of an atom is concentrated in a small central area. He called this area the nucleus. Rutherford later discovered that the nucleus contains positively charged particles. He named the positive particles protons. Rutherford also predicted the existenc... |
Aristotle thought that | (A) atoms exist (B) atoms are uncuttable (C) all matter consists of atoms (D) the idea of atoms is ridiculous | D | A Greek philosopher named Thales, who lived around 600 BCE, has been called the father of science for his ideas about the natural world. He proposed that natural events such as lightning and earthquakes have natural causes. Up until then, people understood such events to be the acts of gods or other supernatural forces... |
Rutherford concluded from his experiments that | (A) all the positive charge of an atom is concentrated in the center (B) positive charge is spread evenly throughout an atom (C) electrons orbit the positively charged nucleus (D) two of the above | D | Rutherford made the same inferences. He concluded that all of the positive charge and virtually all of the mass of an atom are concentrated in one tiny area and the rest of the atom is mostly empty space. Rutherford called the area of concentrated positive charge the nucleus. He predictedand soon discoveredthat the nuc... |
scientist who discovered electrons. | (A) Democritus (B) Aristotle (C) John Dalton (D) J (E) Ernest Rutherford (F) plum pudding model (G) planetary model | D | The next major advance in the history of the atom was the discovery of electrons. These were the first subatomic particles to be identified. They were discovered in 1897 by a British physicist named J. J. Thomson. You can learn more about Thomson and his discovery at this online exhibit: . |
philosopher who thought the idea of the atom was ridiculous | (A) Democritus (B) Aristotle (C) John Dalton (D) J (E) Ernest Rutherford (F) plum pudding model (G) planetary model | B | Democritus was an important philosopher, but he was less influential than another Greek philosopher named Aristo- tle, who lived about 100 years after Democritus. Aristotle rejected Democritus idea of the atom. In fact, Aristotle thought the idea was ridiculous. Unfortunately, Aristotles opinion was accepted for more t... |
Thomsons atomic model | (A) Democritus (B) Aristotle (C) John Dalton (D) J (E) Ernest Rutherford (F) plum pudding model (G) planetary model | F | Thomson knew that atoms are neutral in electric charge. So how could atoms contain negative particles? Thomson thought that the rest of the atom must be positive to cancel out the negative charge. He said that an atom is like a plum pudding, which has plums scattered through it. Thats why Thomsons model of the atom is ... |
Thomson aimed a beam of alpha particles at gold foil. | (A) true (B) false | B | In 1899, Rutherford discovered that some elements give off positively charged particles. He named them alpha particles (a). In 1911, he used alpha particles to study atoms. He aimed a beam of alpha particles at a very thin sheet of gold foil. Outside the foil, he placed a screen of material that glowed when alpha parti... |
philosopher who introduced the idea of the atom | (A) Democritus (B) Aristotle (C) John Dalton (D) J (E) Ernest Rutherford (F) plum pudding model (G) planetary model | A | Democritus was an important philosopher, but he was less influential than another Greek philosopher named Aristo- tle, who lived about 100 years after Democritus. Aristotle rejected Democritus idea of the atom. In fact, Aristotle thought the idea was ridiculous. Unfortunately, Aristotles opinion was accepted for more t... |
The plums in the plum pudding model represent protons. | (A) true (B) false | B | Thomson knew that atoms are neutral in electric charge. So how could atoms contain negative particles? Thomson thought that the rest of the atom must be positive to cancel out the negative charge. He said that an atom is like a plum pudding, which has plums scattered through it. Thats why Thomsons model of the atom is ... |
Rutherfords atomic model | (A) Democritus (B) Aristotle (C) John Dalton (D) J (E) Ernest Rutherford (F) plum pudding model (G) planetary model | G | Rutherfords discoveries meant that Thomsons plum pudding model was incorrect. Positive charge is not spread evenly throughout an atom. Instead, it is all concentrated in the tiny nucleus. The rest of the atom is empty space except for the electrons scattered through it. In Rutherfords model of the atom, which is shown ... |
scientist who developed atomic theory | (A) Democritus (B) Aristotle (C) John Dalton (D) J (E) Ernest Rutherford (F) plum pudding model (G) planetary model | C | Around 1800, a British chemist named John Dalton revived Democrituss early ideas about the atom. Dalton is pictured in Figure 5.8. He made a living by teaching and just did research in his spare time. Nonetheless, from his research results, he developed one of the most important theories in science. |
The planets in the planetary model represent electrons. | (A) true (B) false | A | Today, these ideas about electrons are represented by the electron cloud model. The electron cloud is an area around the nucleus where electrons are likely to be. Figure 5.17 shows an electron cloud model for a helium atom. |
scientist who discovered the nucleus | (A) Democritus (B) Aristotle (C) John Dalton (D) J (E) Ernest Rutherford (F) plum pudding model (G) planetary model | E | A physicist from New Zealand named Ernest Rutherford made the next major discovery about atoms. He discovered the nucleus. You can watch a video about Rutherford and his discovery at this URL: MEDIA Click image to the left or use the URL below. URL: |
The first subatomic particle to be discovered was the proton. | (A) true (B) false | B | Scientists have long wanted to find the most basic building blocks of the universe. They asked, what are the fundamental particles of matter that cannot be subdivided into smaller, simpler particles, and what holds these particles together? The quest for fundamental particles began thousands of years ago. Scientists th... |
Dalton thought that all substances are made of atoms. | (A) true (B) false | A | From his research, Dalton developed a theory about atoms. Daltons atomic theory consists of three basic ideas: All substances are made of atoms. Atoms are the smallest particles of matter. They cannot be divided into smaller particles, created, or destroyed. All atoms of the same element are alike and have the same mas... |
The history of the atom began almost | (A) 2500 years ago (B) 700 years ago (C) 500 years ago (D) 100 years ago | A | The history of the atom begins around 450 B.C. with a Greek philosopher named Democritus (see Figure 5.7). Democritus wondered what would happen if you cut a piece of matter, such as an apple, into smaller and smaller pieces. He thought that a point would be reached where matter could not be cut into still smaller piec... |
Daltons research provided evidence that | (A) atoms exist (B) gases consist of tiny particles in constant motion (C) a compound always consists of the same elements in the same ratio (D) all of the above | D | Dalton did many experiments that provided evidence for the existence of atoms. For example: He investigated pressure and other properties of gases, from which he inferred that gases must consist of tiny, individual particles that are in constant, random motion. He researched the properties of compounds, which are subst... |
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