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Which statement is part of Daltons atomic theory? | (A) All substances are made of atoms (B) Atoms can be divided into smaller particles (C) Atoms form when compounds join together (D) All atoms of the same element have the same number of protons | 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... |
Daltons atomic models were most similar to | (A) bowling balls (B) plum puddings (C) planetary orbits (D) blades of a fan | A | Because Dalton thought atoms were the smallest particles of matter, he envisioned them as solid, hard spheres, like billiard (pool) balls, so he used wooden balls to model them. Three of his model atoms are pictured in the Figure and used to model compounds. Q: When scientists discovered smaller particles inside the at... |
Thomsons research involved | (A) gold foil and alpha particles (B) electric current and a vacuum tube (C) gases and pressure (D) neutrons and back scattering | B | Thomson was interested in electricity. He did experiments in which he passed an electric current through a vacuum tube. The experiments are described in Figure 5.10. Thomsons experiments showed that an electric current consists of flowing, negatively charged particles. Why was this discovery important? Many scientists ... |
In the plum pudding model of the atom, the plums represent | (A) protons (B) neutrons (C) nuclei (D) electrons | D | 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 ... |
In the planetary model, the planets represent | (A) alpha particles (B) gold atoms (C) electrons (D) positive charges | C | The ancient Greeks thought that Earth was at the center of the universe, as shown in Figure 25.1. The sky had a set of spheres layered on top of one another. Each object in the sky was attached to one of these spheres. The object moved around Earth as that sphere rotated. These spheres contained the Moon, the Sun, and ... |
Aristotle rejected Democrituss idea of the atom. | (A) true (B) false | 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... |
Dalton thought that atoms could be created or destroyed. | (A) true (B) false | B | 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... |
Daltons atomic theory was later completely rejected. | (A) true (B) false | B | 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... |
Ernest Rutherford discovered neutrons. | (A) true (B) false | B | 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: |
Thomson showed that electric charge is carried by particles of matter. | (A) true (B) false | A | Thomson was interested in electricity. He did experiments in which he passed an electric current through a vacuum tube. The experiments are described in Figure 5.10. Thomsons experiments showed that an electric current consists of flowing, negatively charged particles. Why was this discovery important? Many scientists ... |
The pudding in the plum pudding model represents positive charge. | (A) true (B) false | A | 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 ... |
Democritus represented atoms with solid wooden balls. | (A) true (B) false | B | Dalton incorrectly thought that atoms are tiny solid particles of matter. He used solid wooden balls to model them. The sketch in the Figure 5.9 shows how Daltons model atoms looked. He made holes in the balls so they could be joined together with hooks. In this way, the balls could be used to model compounds. When lat... |
In the gold foil experiments, most of the alpha particles were deflected backward from the 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... |
Dalton was the first scientist to observe atoms with a microscope. | (A) true (B) false | B | Around 1800, the English chemist John Dalton brought back Democritus ancient idea of the atom. You can see a picture of Dalton 1.1. Dalton grew up in a working-class family. As an adult, he made a living by teaching and just did research in his spare time. Nonetheless, from his research he developed one of the most imp... |
Electrons flow through a vacuum tube from the negative end to the positive end. | (A) true (B) false | A | Thomson was interested in electricity. He did experiments in which he passed an electric current through a vacuum tube. The experiments are described in Figure 5.10. Thomsons experiments showed that an electric current consists of flowing, negatively charged particles. Why was this discovery important? Many scientists ... |
Which statement about energy levels is false? | (A) They are located at fixed distances from the nucleus of the atom (B) They are the only places where electrons can be found (C) They have more energy when they are farther from the nucleus (D) They all have the same number of electrons | D | Basic to Bohrs model is the idea of energy levels. Energy levels are areas located at fixed distances from the nucleus of the atom. They are the only places where electrons can be found. Energy levels are a little like rungs on a ladder. You can stand on one rung or another but not between the rungs. The same goes for ... |
What are orbitals? | (A) regions in the electron cloud where electrons are most likely to be (B) fixed paths in which electrons orbit the nucleus (C) places where electron waves are unstable (D) none of the above | A | The atomic model above is useful for some purposes, but its too simple when it comes to the location of electrons. In reality, its impossible to say what path an electron will follow. Instead, its only possible to describe the chances of finding an electron in a certain region around the nucleus. The region where an el... |
An electron emits energy when it jumps from | (A) a proton to a neutron (B) an electron cloud to an orbital (C) an orbital to the atomic nucleus (D) a higher energy level to a lower energy level | D | 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 steps of a staircase. You can stand on one step o... |
How many electrons can there be in energy level 1? | (A) 0 (B) 1 (C) 2 (D) 3 | C | The smallest atoms are hydrogen atoms. They have just one electron orbiting the nucleus. That one electron is in the first energy level. Bigger atoms have more electrons. Electrons are always added to the lowest energy level first until it has the maximum number of electrons possible. Then electrons are added to the ne... |
Bohrs model of the atom differs from Rutherfords model in the | (A) placement of the nucleus (B) charge of the nucleus (C) number of electrons (D) location of electrons | D | 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 ... |
Bohrs research focused on | (A) electrons (B) neutrons (C) protons (D) none of the above | A | Bohrs research focused on electrons. In 1913, he discovered evidence that the orbits of electrons are located at fixed distances from the nucleus. Remember, Rutherford thought that electrons orbit the nucleus at random. Figure 5.14 shows Bohrs model of the atom. |
Which statement about energy levels is false? | (A) They are located at fixed distances from the nucleus (B) They are the only places where electrons can be found (C) They have more energy when they are farther from the nucleus (D) There are only two of them | D | Basic to Bohrs model is the idea of energy levels. Energy levels are areas located at fixed distances from the nucleus of the atom. They are the only places where electrons can be found. Energy levels are a little like rungs on a ladder. You can stand on one rung or another but not between the rungs. The same goes for ... |
Fireworks give off light energy when their electrons | (A) flow to different atoms (B) jump to a lower energy level (C) produce electric current (D) change from matter to energy | B | Bohrs idea of energy levels is still useful today. It helps explain how matter behaves. For example, when chemicals in fireworks explode, their atoms absorb energy. Some of their electrons jump to a higher energy level. When the electrons move back to their original energy level, they give off the energy as light. Diff... |
The focus of Bohrs research was the nucleus. | (A) true (B) false | B | Bohrs research focused on electrons. In 1913, he discovered evidence that the orbits of electrons are located at fixed distances from the nucleus. Remember, Rutherford thought that electrons orbit the nucleus at random. Figure 5.14 shows Bohrs model of the atom. |
Energy levels farther from the nucleus have | (A) less energy (B) more orbitals (C) a greater maximum number of electrons (D) two of the above | D | 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 steps of a staircase. You can stand on one step o... |
Bohr rejected modern atomic theory. | (A) true (B) false | B | Bohrs research focused on electrons. In 1913, he discovered evidence that the orbits of electrons are located at fixed distances from the nucleus. Remember, Rutherford thought that electrons orbit the nucleus at random. Figure 5.14 shows Bohrs model of the atom. |
How many orbitals are there at energy level 3? | (A) 1 (B) 4 (C) 9 (D) 16 | C | The smallest atoms are hydrogen atoms. They have just one electron orbiting the nucleus. That one electron is in the first energy level. Bigger atoms have more electrons. Electrons are always added to the lowest energy level first until it has the maximum number of electrons possible. Then electrons are added to the ne... |
Electrons bend around the nucleus instead of falling toward it because electrons behave like | (A) protons (B) orbitals (C) clouds (D) waves | D | In the 1920s, physicists discovered that electrons do not travel in fixed paths. In fact, they found that electrons only have a certain chance of being in any particular place. They could only describe where electrons are with mathematical formulas. Thats because electrons have wave-like properties as well as propertie... |
There is a maximum of two energy levels in an atom. | (A) true (B) false | B | The smallest atoms are hydrogen atoms. They have just one electron orbiting the nucleus. That one electron is in the first energy level. Bigger atoms have more electrons. Electrons are always added to the lowest energy level first until it has the maximum number of electrons possible. Then electrons are added to the ne... |
Where would you not be likely to find electrons in an atom? | (A) inside the nucleus (B) attached to the nucleus (C) between energy levels (D) all of the above | D | In the 1920s, physicists discovered that electrons do not travel in fixed paths. In fact, they found that electrons only have a certain chance of being in any particular place. They could only describe where electrons are with mathematical formulas. Thats because electrons have wave-like properties as well as propertie... |
Electrons fall toward the nucleus because they behave like waves. | (A) true (B) false | B | In the 1920s, physicists discovered that electrons do not travel in fixed paths. In fact, they found that electrons only have a certain chance of being in any particular place. They could only describe where electrons are with mathematical formulas. Thats because electrons have wave-like properties as well as propertie... |
Energy levels are located between the orbitals of atoms. | (A) true (B) false | B | Basic to Bohrs model is the idea of energy levels. Energy levels are areas located at fixed distances from the nucleus of the atom. They are the only places where electrons can be found. Energy levels are a little like rungs on a ladder. You can stand on one rung or another but not between the rungs. The same goes for ... |
Energy level 1 has the most energy. | (A) true (B) false | B | 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 steps of a staircase. You can stand on one step o... |
Electrons can move from one energy level to another. | (A) true (B) false | A | 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 steps of a staircase. You can stand on one step o... |
Scientists can now determine the exact location of any given electron. | (A) true (B) false | B | In the 1920s, physicists discovered that electrons do not travel in fixed paths. In fact, they found that electrons only have a certain chance of being in any particular place. They could only describe where electrons are with mathematical formulas. Thats because electrons have wave-like properties as well as propertie... |
Electrons are attracted to the nucleus because of the strong force. | (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... |
Some regions of the electron cloud are denser than others. | (A) true (B) false | A | Some regions of the electron cloud are denser than others. The denser regions are areas where electrons are most likely to be. These regions are called orbitals. Each orbital has a maximum of just two electrons. Different energy levels in the cloud have different numbers of orbitals. Therefore, different energy levels ... |
There is a maximum of two orbitals per energy level. | (A) true (B) false | B | The smallest atoms are hydrogen atoms. They have just one electron orbiting the nucleus. That one electron is in the first energy level. Bigger atoms have more electrons. Electrons are always added to the lowest energy level first until it has the maximum number of electrons possible. Then electrons are added to the ne... |
Fireworks give off light when their electrons split in two. | (A) true (B) false | B | Bohrs idea of energy levels is still useful today. It helps explain how matter behaves. For example, when chemicals in fireworks explode, their atoms absorb energy. Some of their electrons jump to a higher energy level. When the electrons move back to their original energy level, they give off the energy as light. Diff... |
Since the 1920s, physicists have known that electrons travel in fixed paths. | (A) true (B) false | B | In the 1920s, physicists discovered that electrons do not travel in fixed paths. In fact, they found that electrons only have a certain chance of being in any particular place. They could only describe where electrons are with mathematical formulas. Thats because electrons have wave-like properties as well as propertie... |
Wavelike particles in the atom exist only where the wave is stable. | (A) true (B) false | A | In the 1920s, physicists discovered that electrons do not travel in fixed paths. In fact, they found that electrons only have a certain chance of being in any particular place. They could only describe where electrons are with mathematical formulas. Thats because electrons have wave-like properties as well as propertie... |
All energy levels have the same maximum number of electrons. | (A) true (B) false | B | Some regions of the electron cloud are denser than others. The denser regions are areas where electrons are most likely to be. These regions are called orbitals. Each orbital has a maximum of just two electrons. Different energy levels in the cloud have different numbers of orbitals. Therefore, different energy levels ... |
number of orbitals in the first energy level | (A) electron cloud (B) energy level (C) Rutherford (D) Bohr (E) electron (F) two (G) one | G | Some regions of the electron cloud are denser than others. The denser regions are areas where electrons are most likely to be. These regions are called orbitals. Each orbital has a maximum of just two electrons. Different energy levels in the cloud have different numbers of orbitals. Therefore, different energy levels ... |
area surrounding the nucleus of an atom where electrons are likely to be | (A) electron cloud (B) energy level (C) Rutherford (D) Bohr (E) electron (F) two (G) one | 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 thought that electrons orbit the nucleus like planets orbit the sun | (A) electron cloud (B) energy level (C) Rutherford (D) Bohr (E) electron (F) two (G) one | C | Bohrs research focused on electrons. In 1913, he discovered evidence that the orbits of electrons are located at fixed distances from the nucleus. Remember, Rutherford thought that electrons orbit the nucleus at random. Figure 5.14 shows Bohrs model of the atom. |
maximum number of electrons per orbital | (A) electron cloud (B) energy level (C) Rutherford (D) Bohr (E) electron (F) two (G) one | F | Some regions of the electron cloud are denser than others. The denser regions are areas where electrons are most likely to be. These regions are called orbitals. Each orbital has a maximum of just two electrons. Different energy levels in the cloud have different numbers of orbitals. Therefore, different energy levels ... |
area located at a fixed distance from the nucleus of an atom where electrons can orbit the nucleus | (A) electron cloud (B) energy level (C) Rutherford (D) Bohr (E) electron (F) two (G) one | B | Bohrs research focused on electrons. In 1913, he discovered evidence that the orbits of electrons are located at fixed distances from the nucleus. Remember, Rutherford thought that electrons orbit the nucleus at random. Figure 5.14 shows Bohrs model of the atom. |
wavelike particles that move around the nucleus of an atom | (A) electron cloud (B) energy level (C) Rutherford (D) Bohr (E) electron (F) two (G) one | E | At the center of an atom is the nucleus (plural, nuclei). The nucleus contains most of the atoms mass. However, in size, its just a tiny part of the atom. The model in Figure 5.1 is not to scale. If an atom were the size of a football stadium, the nucleus would be only about the size of a pea. The nucleus, in turn, con... |
scientist who discovered energy levels | (A) electron cloud (B) energy level (C) Rutherford (D) Bohr (E) electron (F) two (G) one | D | Bohrs idea of energy levels is still useful today. It helps explain how matter behaves. For example, when chemicals in fireworks explode, their atoms absorb energy. Some of their electrons jump to a higher energy level. When the electrons move back to their original energy level, they give off the energy as light. Diff... |
Mendeleev organized the elements based on their | (A) atomic number (B) number of protons (C) atomic mass (D) number of neutrons | C | In the 1860s, a scientist named Dmitri Mendeleev also saw the need to organize the elements. He created a table in which he arranged all of the elements by increasing atomic mass from left to right across each row. When he placed eight elements in each row and then started again in the next row, each column of the tabl... |
In the modern periodic table, atomic number | (A) increases from top to bottom within each period (B) increases from left to right within each group (C) is the same within each group but not between groups (D) none of the above | D | In the modern periodic table, elements are organized by atomic number. The atomic number is the number of protons in an atom of an element. This number is unique for each element, so it seems like an obvious way to organize the elements. (Mendeleev used atomic mass instead of atomic number because protons had not yet b... |
The shortest period in the periodic table is period | (A) 18 (B) 7 (C) 6 (D) 1 | D | Rows of the modern periodic table are called periods, as they are in Mendeleevs table. From left to right across a period, each element has one more proton than the element before it. Some periods in the modern periodic table are longer than others. For example, period 1 contains only two elements: hydrogen (H) and hel... |
All but one of the elements on the left side of the periodic table are | (A) metalloids (B) liquids (C) metals (D) gases | C | Rows of the modern table are called periods, as they are in Mendeleevs table. From left to right across a period, each element has one more proton than the element before it. In each period, elements change from metals on the left side of the table, to metalloids, and then to nonmetals on the right. Figure 6.4 shows th... |
Which statement is true about any group in the periodic table? | (A) It includes metals (B) metalloids (C) and nonmetals (D) b It includes elements with similar properties (E) c It includes gases (F) liquids (G) and solids (H) d It contains 18 different elements | B | Columns of the modern table are called groups, as they are in Mendeleevs table. However, the modern table has many more groups18 compared with just 8 in Mendeleevs table. Elements in the same group have similar properties. For example, all elements in group 18 are colorless, odorless gases, such as neon (Ne). (Neon is ... |
number of protons in an atom | (A) group (B) period (C) atomic number (D) atomic mass (E) chemical symbol (F) Mendeleevs periodic table (G) modern periodic table | C | The number of protons in an atom is called its atomic number. This number is very important because it is unique for atoms of a given element. All atoms of an element have the same number of protons, and every element has a different number of protons in its atoms. For example, all helium atoms have two protons, and no... |
row of the periodic table | (A) group (B) period (C) atomic number (D) atomic mass (E) chemical symbol (F) Mendeleevs periodic table (G) modern periodic table | B | You can see how Mendeleev organized the elements in Figure 6.2. From left to right across each row, elements are arranged by increasing atomic mass. Mendeleev discovered that if he placed eight elements in each row and then continued on to the next row, the columns of the table would contain elements with similar prope... |
table based on the atomic number of elements | (A) group (B) period (C) atomic number (D) atomic mass (E) chemical symbol (F) Mendeleevs periodic table (G) modern periodic table | G | A periodic table is still used today to organize the elements. You can see a simple version of the modern periodic table in the Figure 1.1. The modern table is based on Mendeleevs table, except the modern table arranges the elements by increasing atomic number instead of atomic mass. Atomic number is the number of prot... |
Mendeleev left spaces in his periodic table for unknown elements. | (A) true (B) false | A | Did you notice the blanks in Mendeleevs table? They are spaces that Mendeleev left blank for elements that had not yet been discovered when he created his table. He predicted that these missing elements would eventually be discovered. Based on their position in the table, he even predicted their properties. For example... |
how an element is represented in the periodic table | (A) group (B) period (C) atomic number (D) atomic mass (E) chemical symbol (F) Mendeleevs periodic table (G) modern periodic table | E | Rows of the modern periodic table are called periods, as they are in Mendeleevs table. From left to right across a period, each element has one more proton than the element before it. Some periods in the modern periodic table are longer than others. For example, period 1 contains only two elements: hydrogen (H) and hel... |
The modern periodic table is the same as Mendeleevs table but with more elements. | (A) true (B) false | B | A periodic table is still used today to organize the elements. You can see a simple version of the modern periodic table in the Figure 1.1. The modern table is based on Mendeleevs table, except the modern table arranges the elements by increasing atomic number instead of atomic mass. Atomic number is the number of prot... |
table based on the atomic mass of elements | (A) group (B) period (C) atomic number (D) atomic mass (E) chemical symbol (F) Mendeleevs periodic table (G) modern periodic table | F | A periodic table is still used today to organize the elements. You can see a simple version of the modern periodic table in the Figure 1.1. The modern table is based on Mendeleevs table, except the modern table arranges the elements by increasing atomic number instead of atomic mass. Atomic number is the number of prot... |
column of the periodic table | (A) group (B) period (C) atomic number (D) atomic mass (E) chemical symbol (F) Mendeleevs periodic table (G) modern periodic table | A | Columns of the modern table are called groups, as they are in Mendeleevs table. However, the modern table has many more groups18 compared with just 8 in Mendeleevs table. Elements in the same group have similar properties. For example, all elements in group 18 are colorless, odorless gases, such as neon (Ne). (Neon is ... |
The modern periodic table has more than 100 elements. | (A) true (B) false | A | All known matter can be divided into a little more than 100 different substances called elements. |
amount of matter in an atom | (A) group (B) period (C) atomic number (D) atomic mass (E) chemical symbol (F) Mendeleevs periodic table (G) modern periodic table | D | Here is a riddle for you to ponder: What do you and a tiny speck of dust in outer space have in common? Think you know the answer? Both you and the speck of dust consist of matter. So does the ground beneath your feet. In fact, everything you can see and touch is made of matter. The only things that are not matter are ... |
Elements called actinides are in period 7 of the periodic table. | (A) true (B) false | A | Transition metals include the elements that are most often placed below the periodic table (the pink- and purple- shaded elements in the Figure 1.1). Those that follow lanthanum (La) are called lanthanides. They are all relatively reactive for transition metals. Those that follow actinium (Ac) are called actinides. The... |
Elements in the same period of the periodic table have similar properties. | (A) true (B) false | B | You can see how Mendeleev organized the elements in Figure 6.2. From left to right across each row, elements are arranged by increasing atomic mass. Mendeleev discovered that if he placed eight elements in each row and then continued on to the next row, the columns of the table would contain elements with similar prope... |
Mendeleev developed his periodic table in the 1860s. | (A) true (B) false | A | In the 1860s, a scientist named Dmitri Mendeleev also saw the need to organize the elements. He created a table in which he arranged all of the elements by increasing atomic mass from left to right across each row. When he placed eight elements in each row and then started again in the next row, each column of the tabl... |
Mendeleev named the columns of his table periods. | (A) true (B) false | B | In the 1860s, a scientist named Dmitri Mendeleev also saw the need to organize the elements. He created a table in which he arranged all of the elements by increasing atomic mass from left to right across each row. When he placed eight elements in each row and then started again in the next row, each column of the tabl... |
Elements within a group of the periodic table are identical to each other. | (A) true (B) false | B | Columns of the modern table are called groups, as they are in Mendeleevs table. However, the modern table has many more groups18 compared with just 8 in Mendeleevs table. Elements in the same group have similar properties. For example, all elements in group 18 are colorless, odorless gases, such as neon (Ne). (Neon is ... |
In Mendeleevs table, each period contains 18 elements. | (A) true (B) false | B | In the 1860s, a scientist named Dmitri Mendeleev also saw the need to organize the elements. He created a table in which he arranged all of the elements by increasing atomic mass from left to right across each row. When he placed eight elements in each row and then started again in the next row, each column of the tabl... |
Mendeleevs used his table to predict unknown elements. | (A) true (B) false | A | Did you notice the blanks in Mendeleevs table? They are spaces that Mendeleev left blank for elements that had not yet been discovered when he created his table. He predicted that these missing elements would eventually be discovered. Based on their position in the table, he even predicted their properties. For example... |
The elements Mendeleev predicted were never discovered. | (A) true (B) false | B | Did you notice the blanks in Mendeleevs table? They are spaces that Mendeleev left blank for elements that had not yet been discovered when he created his table. He predicted that these missing elements would eventually be discovered. Based on their position in the table, he even predicted their properties. For example... |
Lanthanide elements are placed in period 2 of the modern periodic table. | (A) true (B) false | B | Rows of the modern table are called periods, as they are in Mendeleevs table. From left to right across a period, each element has one more proton than the element before it. In each period, elements change from metals on the left side of the table, to metalloids, and then to nonmetals on the right. Figure 6.4 shows th... |
The chemical symbol for lead is Pb. | (A) true (B) false | A | Besides atomic number, the periodic table includes each elements chemical symbol and class. Some tables include other information as well. The chemical symbol consists of one or two letters that come from the chemicals name in English or another language. The first letter is always written in upper case. The second let... |
Most elements in the modern periodic table are metalloids. | (A) true (B) false | B | Groups 13-16 of the periodic table (orange in the Figure 1.1) are the only groups that contain elements classified as metalloids. Unlike other groups of the periodic table, which contain elements in just one class, groups 13-16 contain elements in at least two different classes. In addition to metalloids, they also con... |
Krypton is a gaseous metal in group 18 of the periodic table. | (A) true (B) false | A | Noble gases are nonreactive, nonmetallic elements in group 18 of the periodic table. As you can see in the periodic table below, noble gases include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). All noble gases are colorless and odorless. They also have low boiling points, explaining why... |
Scientist first started looking for a way to organize the elements in the | (A) 1700s (B) late 1800s (C) early 1900s (D) 1980s | A | In the 1860s, a scientist named Dmitri Mendeleev also saw the need to organize the elements. He created a table in which he arranged all of the elements by increasing atomic mass from left to right across each row. When he placed eight elements in each row and then started again in the next row, each column of the tabl... |
How many groups are there in Mendeleevs periodic table? | (A) 18 (B) 16 (C) 12 (D) 8 | D | Columns of the modern table are called groups, as they are in Mendeleevs table. However, the modern table has many more groups18 compared with just 8 in Mendeleevs table. Elements in the same group have similar properties. For example, all elements in group 18 are colorless, odorless gases, such as neon (Ne). (Neon is ... |
Examples that illustrate the meaning of periodic include | (A) phases of the moon (B) day and night (C) months of the year (D) all of the above | D | You can see how Mendeleev organized the elements in Figure 6.2. From left to right across each row, elements are arranged by increasing atomic mass. Mendeleev discovered that if he placed eight elements in each row and then continued on to the next row, the columns of the table would contain elements with similar prope... |
How many elements are represented in the modern periodic table? | (A) fewer than 50 (B) exactly 18 (C) about 65 (D) more than 100 | D | Rows of the modern table are called periods, as they are in Mendeleevs table. From left to right across a period, each element has one more proton than the element before it. In each period, elements change from metals on the left side of the table, to metalloids, and then to nonmetals on the right. Figure 6.4 shows th... |
Which of the following could be the chemical symbol of an element? | (A) SI (B) si (C) Si (D) iS | C | In the Figure 1.1, each element is represented by its chemical symbol, which consists of one or two letters. The first letter of the symbol is always written in upper case, and the second letterif there is oneis always written in lower case. For example, the symbol for copper is Cu. It stands for cuprum, which is the L... |
Elements on the right side of the periodic table are | (A) metals (B) metalloids (C) nonmetals (D) actinides | C | Rows of the modern table are called periods, as they are in Mendeleevs table. From left to right across a period, each element has one more proton than the element before it. In each period, elements change from metals on the left side of the table, to metalloids, and then to nonmetals on the right. Figure 6.4 shows th... |
Which sentence is true about periods of the periodic table? | (A) All the periods are the same length (B) There are a total of 18 periods (C) Some periods are longer than others (D) two of the above | C | Rows of the modern table are called periods, as they are in Mendeleevs table. From left to right across a period, each element has one more proton than the element before it. In each period, elements change from metals on the left side of the table, to metalloids, and then to nonmetals on the right. Figure 6.4 shows th... |
Most metals are | (A) shiny (B) good conductors of heat (C) solids are room temperature (D) all of the above | D | Metals are elements that are good conductors of electricity. They are the largest of the three classes of elements. In fact, most elements are metals. Look back at the modern periodic table (Figure 6.3) in this chapters lesson "How Elements Are Organized." Find the metals in the table. They are all the elements that ar... |
Most metals are | (A) dull (B) brittle (C) ductile (D) all of the above | C | Metals are elements that are good conductors of electricity. They are the largest of the three classes of elements. In fact, most elements are metals. Look back at the modern periodic table (Figure 6.3) in this chapters lesson "How Elements Are Organized." Find the metals in the table. They are all the elements that ar... |
If an element is ductile, this means that it can be | (A) used as an insulator (B) pulled into long thin shapes (C) used to conduct electricity (D) crushed into a powder | B | The valence electrons surrounding metal ions are constantly moving. This makes metals good conductors of electricity. The lattice-like structure of metal ions is strong but quite flexible. This allows metals to bend without breaking. Metals are both ductile (can be shaped into wires) and malleable (can be shaped into t... |
A nonmetal is an element that | (A) exists only as a gas or liquid (B) is completely unreactive (C) cannot conduct electricity (D) is shiny and malleable | C | Nonmetals are elements that generally do not conduct electricity. They are one of three classes of elements (the other two classes are metals and metalloids.) Nonmetals are the second largest of the three classes after metals. They are the elements located on the right side of the periodic table. Q: From left to right ... |
Nonmetals tend to have properties that are | (A) very similar to the properties of metals (B) in between those of metals and metalloids (C) more variable than the properties of metals (D) none of the above | C | As their name suggests, nonmetals generally have properties that are very different from the properties of metals. Properties of nonmetals include a relatively low boiling point, which explains why many of them are gases at room temperature. However, some nonmetals are solids at room temperature, including the three pi... |
Which of the following elements is a metal? | (A) phosphorus (B) selenium (C) lithium (D) boron | C | Metals are elements that are good conductors of electricity. They are the largest of the three classes of elements. In fact, most elements are metals. Look back at the modern periodic table (Figure 6.3) in this chapters lesson "How Elements Are Organized." Find the metals in the table. They are all the elements that ar... |
Which statement about valence electrons is true? | (A) They are located in the outer energy level of an atom (B) They are potentially involved in chemical reactions (C) They determine whether an element can conduct electricity (D) all of the above | D | Valence electrons are the electrons in the outer energy level of an atom that can participate in interactions with other atoms. Valence electrons are generally the electrons that are farthest from the nucleus. As a result, they may be attracted as much or more by the nucleus of another atom than they are by their own n... |
Solid nonmetals are | (A) malleable (B) brittle (C) dull (D) two of the above | D | Nonmetals are elements that do not conduct electricity. They are the second largest class of elements. Find the nonmetals in Figure 6.3. They are all the elements on the right side of the table that are color-coded green. Examples of nonmetals include helium (He), carbon (C), and oxygen (O). Nonmetals generally have pr... |
Which of the following elements is a nonmetal? | (A) sulfur (B) aluminum (C) silver (D) zinc | A | Nonmetals are elements that do not conduct electricity. They are the second largest class of elements. Find the nonmetals in Figure 6.3. They are all the elements on the right side of the table that are color-coded green. Examples of nonmetals include helium (He), carbon (C), and oxygen (O). Nonmetals generally have pr... |
If an element is malleable, this means that it can | (A) be formed into long thin shapes like wires (B) be formed into thin sheets without breaking (C) be used to conduct electric current (D) be used as an electric insulator | B | The valence electrons surrounding metal ions are constantly moving. This makes metals good conductors of electricity. The lattice-like structure of metal ions is strong but quite flexible. This allows metals to bend without breaking. Metals are both ductile (can be shaped into wires) and malleable (can be shaped into t... |
Which of the following elements is a metalloid? | (A) copper (B) helium (C) phosphorus (D) germanium | D | Metalloids are the smallest class of elements. (The other two classes of elements are metals and nonmetals). There are just six metalloids. In addition to silicon, they include boron, germanium, arsenic, antimony, and tellurium. Metalloids fall between metals and nonmetals in the periodic table. They also fall between ... |
Which element has a completely filled outer energy level? | (A) lithium (B) boron (C) fluorine (D) neon | D | Electrons in the outermost energy level of an atom have a special significance. These electrons are called valence electrons, and they determine many of the properties of an atom. An atom is most stable if its outermost energy level contains as many electrons as it can hold. For example, helium has two electrons, both ... |
class of elements that do not conduct electricity | (A) metals (B) metalloids (C) nonmetals (D) mercury (E) ductile (F) bromine (G) brittle | C | Nonmetals are elements that do not conduct electricity. They are the second largest class of elements. Find the nonmetals in Figure 6.3. They are all the elements on the right side of the table that are color-coded green. Examples of nonmetals include helium (He), carbon (C), and oxygen (O). Nonmetals generally have pr... |
word that describes most solid nonmetals | (A) metals (B) metalloids (C) nonmetals (D) mercury (E) ductile (F) bromine (G) brittle | G | Nonmetals are elements that do not conduct electricity. They are the second largest class of elements. Find the nonmetals in Figure 6.3. They are all the elements on the right side of the table that are color-coded green. Examples of nonmetals include helium (He), carbon (C), and oxygen (O). Nonmetals generally have pr... |
smallest class of elements | (A) metals (B) metalloids (C) nonmetals (D) mercury (E) ductile (F) bromine (G) brittle | 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 ... |
All metalloids are solids are room temperature. | (A) true (B) false | A | As their name suggests, nonmetals generally have properties that are very different from the properties of metals. Properties of nonmetals include a relatively low boiling point, which explains why many of them are gases at room temperature. However, some nonmetals are solids at room temperature, including the three pi... |
only nonmetal that is a liquid at room temperature | (A) metals (B) metalloids (C) nonmetals (D) mercury (E) ductile (F) bromine (G) brittle | F | As their name suggests, nonmetals generally have properties that are very different from the properties of metals. Properties of nonmetals include a relatively low boiling point, which explains why many of them are gases at room temperature. However, some nonmetals are solids at room temperature, including the three pi... |
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