Chapter Menu Lesson 1: Organization of the Periodic Table Lesson 2: Isotopes and Radioactivity Lesson 3: Physical Properties and Changes Click on a hyperlink to view the corresponding lesson.

7.1 Organization of the Periodic Table group metallic luster conductivity halogen noble gas

How are the elements arranged? 7.1 Organization of the Periodic Table How are the elements arranged? The periodic table contains information about the structures and characteristics of the elements. Elements are arranged in the periodic table in order of their atomic number.

How are the elements arranged? (cont.)

7.1 Organization of the Periodic Table

7.1 Organization of the Periodic Table Periods A horizontal row of elements in the periodic table is called a period. The atomic numbers increase by one from left to right across a period.

7.1 Organization of the Periodic Table Periods (cont.) Elements are organized into horizontal periods and vertical groups.

7.1 Organization of the Periodic Table Groups A vertical column of elements in the periodic table is called a group. Groups are number 1–18 across the top of the periodic table. Elements in the same group have similar properties. How is an atom’s structure related to its position on the periodic table?

The Lanthanide and Actinide Series 7.1 Organization of the Periodic Table The Lanthanide and Actinide Series The two rows of elements at the bottom of the table are the Lanthanide Series and the Actinide Series.

7.1 Organization of the Periodic Table Metals Elements that are on the left side and in the middle of the periodic table are metals.

Metals (cont.) Metallic refers to the properties of common metals. 7.1 Organization of the Periodic Table Metals (cont.) Metallic refers to the properties of common metals. Luster, or shine, is one property of metals. Metals are also ductile and malleable. Conductivity is the ability of a material to transfer electricity or thermal energy—metals are good conductors.

7.1 Organization of the Periodic Table Metals (cont.)

7.1 Organization of the Periodic Table Nonmetals Elements on the right side of the periodic table are nonmetals.

7.1 Organization of the Periodic Table Nonmetals (cont.) Nonmetals exhibit properties that are the opposite of metals. They are poor conductors of heat and electricity, are brittle, and do not have luster. Nonmetals make up most of the matter in the living world. The most reactive nonmetals are the halogens in Group 17.

Semimetals A few elements are semimetals, or metalloids. 7.1 Organization of the Periodic Table Semimetals A few elements are semimetals, or metalloids.

7.1 Organization of the Periodic Table Semimetals (cont.) Semimetals have the properties of both metals and nonmetals. Semimetals conduct electricity but not as well as metals.

Noble Gases Group 18 elements are the noble gases. 7.1 Organization of the Periodic Table Noble Gases Group 18 elements are the noble gases. Noble gases are extremely stable by themselves and occur in nature as single atoms.

7.1 Organization of the Periodic Table Other Periodic Tables A variety of periodic tables are designed to provide the information needed by different groups of people.

If a substance transfers electricity easily, it is said to be ____. 7.1 Organization of the Periodic Table A B C D If a substance transfers electricity easily, it is said to be ____. A malleable B conductive C metalloid D ductile Lesson 1 Review

The most reactive nonmetals are the ____ in Group 17. A noble gases 7.1 Organization of the Periodic Table A B C D The most reactive nonmetals are the ____ in Group 17. A noble gases B halogens C semimetals D Actinide series Lesson 1 Review

Fluorine has properties most similar to ____. A oxygen B neon 7.1 Organization of the Periodic Table A B C D Fluorine has properties most similar to ____. A oxygen B neon C lithium D chlorine Lesson 1 Review

End of Lesson 1

7.2 Isotopes and Radioactivity radioactive decay radioactive transmutation radioactive element half-life synthetic element particle accelerator

Isotopes—Different Numbers of Neutrons

7.2 Isotopes and Radioactivity How Many Neutrons Isotopes with more neutrons are heavier than isotopes with fewer neutrons.

What determines properties? 7.2 Isotopes and Radioactivity What determines properties? The number of electrons and how they are arranged determines chemical properties of an element.

What is radioactive decay? 7.2 Isotopes and Radioactivity What is radioactive decay? Radioactive decay occurs when an unstable atomic nucleus changes into another nucleus be emitting one or more particles and energy. A nucleus that is unstable and undergoes radioactive decay is called radioactive.

Gold-foil Experiment and Radioactive Decay 7.2 Isotopes and Radioactivity Gold-foil Experiment and Radioactive Decay An alpha particle, which consists of two protons and two neutrons, was shot at the foil. The four particles were blasted out of an isotope as a single particle. The isotope gained stability.

Gold-foil Experiment and Radioactive Decay (cont.) 7.2 Isotopes and Radioactivity Gold-foil Experiment and Radioactive Decay (cont.) An isotope of americium is shown releasing an alpha particle. After losing two protons, americium becomes the element neptunium.

Radioactive Decay and Transmutation 7.2 Isotopes and Radioactivity Radioactive Decay and Transmutation Some radioactive isotopes decay by changing their neutrons into different particles. Some trap their own electrons and put them into the nucleus. A beta particle is an electron released by the nucleus of an atom. When a beta particle is released, it gains a proton and becomes the element with one higher atomic number.

Radioactive Decay and Transmutation 7.2 Isotopes and Radioactivity Radioactive Decay and Transmutation (cont.) One element changing into another is called transmutation.

Uses of Radioactive Decay 7.2 Isotopes and Radioactivity Uses of Radioactive Decay Radiation can be used to detect and kill cancer cells, kill bacteria, fungi, insects, and other things that cause food to spoil. Antoine-Henri Bequerel exposed film to radioactive materials. Marie Curie separated the radioactive elements in a uranium mineral and discovered polonium and radium.

Radioactive Elements and the Periodic Table 7.2 Isotopes and Radioactivity Radioactive Elements and the Periodic Table Radioactive elements are some of the heavier elements that have no stable isotopes.

7.2 Isotopes and Radioactivity Half-life The half-life of a radioactive element is the time it takes to decay to half its original mass. Some elements have a half life of millions of years, some less than a second.

7.2 Isotopes and Radioactivity Synthetic Elements Synthetic elements are radioactive elements that are made by scientists or created by nuclear reactions. All elements with atomic numbers higher than 92 are synthetic elements and exist only because scientists create them by artificial transmutation.

Particle Accelerators 7.2 Isotopes and Radioactivity Particle Accelerators Particle accelerators are giant machines capable of making particles travel very fast. The particles may meld together with target particles to create a new element with a higher atomic number.

7.2 Isotopes and Radioactivity Element Names Elements are often named to honor the scientists who discovered them.

7.2 Isotopes and Radioactivity B C D The process by which one element changes into another element is called ____. A radioactive decay B alpha particle decay C transmutation D transformation Lesson 2 Review

7.2 Isotopes and Radioactivity B C D How long would an 80 g sample of barium-131 take to decay to 5 g if the half-life is 12 days? A 12 days B 6 days C 36 days D 48 days Lesson 2 Review

Elements with atomic numbers higher than 92 are known as ____. 7.2 Isotopes and Radioactivity A B C D Elements with atomic numbers higher than 92 are known as ____. A synthetic elements B natural elements C metals D semimetals Lesson 2 Review

End of Lesson 2

7.3 Physical Properties and Changes physical property melting point boiling point thermal conductivity electrical conductivity physical change

What is a physical property? 7.3 Physical Properties and Changes What is a physical property? Substances have physical properties that can be described and physical changes that can be observed. A physical property is any characteristic of a material that can be observed without changing the material, such as color, length, or shape. How is an atom’s structure related to its position on the periodic table?

Melting and Boiling Points 7.3 Physical Properties and Changes Melting and Boiling Points The temperature at which a solid changes to a liquid is the melting point. The temperature at which a liquid changes to a gas is the boiling point.

7.3 Physical Properties and Changes Attractive Forces Attractive forces determine the melting and boiling points of a substance. Molecules with weak attraction have low melting and boiling points. Molecules with strong attractions have high melting and boiling points.

Pressure Pressure also affects the boiling point. 7.3 Physical Properties and Changes Pressure Pressure also affects the boiling point. The higher the air pressure, the higher the boiling point.

Density Density is mass per unit volume of a substance. 7.3 Physical Properties and Changes Density Density is mass per unit volume of a substance. The volumes are the same, but the density of the gas is less than the solid or liquid because there are fewer gas particles in the container.

7.3 Physical Properties and Changes Hardness Hardness is a physical property that shows how strongly the particles of a substance are held together. Diamonds are a form of carbon and are the hardest substance found in nature.

7.3 Physical Properties and Changes Hardness (cont.) This table shows the differences between the structures of diamonds and graphite—both composed of carbon atoms.

7.3 Physical Properties and Changes Thermal Conductivity Thermal conductivity is the ability of a material to transfer heat by collisions of its particles. If one part of the metal is heated, the particles move quickly and collide with nearby particles, transferring heat. Gases have low thermal conductivity compared to solids because the particles are spread farther apart and do not collide as often.

7.3 Physical Properties and Changes Gases As Insulators Gases are sometimes sealed in windows because they do not conduct heat as easily as glass—less heat is lost through the window.

Electrical Conductivity 7.3 Physical Properties and Changes Electrical Conductivity Electrical conductivity is the ability of a material to transfer an electric charge.

What is a physical change? 7.3 Physical Properties and Changes What is a physical change? A physical change is any change in the size, shape, or state of matter in which the identity of the substance is not changed. Dissolving is mixing a substance into another substance to form a solution. Mixing is a physical change in which neither substance dissolves into the other.

7.3 Physical Properties and Changes Changes In State Changes in state are also physical changes that are reversible. Melting and freezing Boiling and condensing Sublimation and deposition

When water changes to ice, it is undergoing a ____. A chemical change 7.3 Physical Properties and Changes A B C D When water changes to ice, it is undergoing a ____. A chemical change B physical change C radioactive decay D metallic change Lesson 3 Review

Which of the following is NOT a physical change? 7.3 Physical Properties and Changes A B C D Which of the following is NOT a physical change? A ice melting into water B sugar dissolving into water C sand and sugar mixing D burning a candle Lesson 3 Review

Which of the following is NOT a physical property? A density 7.3 Physical Properties and Changes A B C D Which of the following is NOT a physical property? A density B conductivity C hardness D all are physical properties Lesson 3 Review

End of Lesson 3

Chapter Resources Menu Chapter Assessment California Standards Practice Concepts in Motion Image Bank Science Online Virtual Labs BrainPOP Click on a hyperlink to view the corresponding feature.

Which is a property of metals? A poor conductors B brittle C low melting point D luster Chapter Assessment 1

Which of the following is a noble gas? A nitrogen B oxygen C argon D Which of the following is a noble gas? A nitrogen B oxygen C argon D bromine Chapter Assessment 2

A B C D The half-life of Fermium-249 is 3 minutes. How much of a 20 g sample of Fermium-249 will be left after 9 minutes? A 2.5 g B 5 g C 10 g D 9 g Chapter Assessment 3

Elements in a period are arranged ____. B C D Elements in a period are arranged ____. A by increasing atomic number right to left B by increasing atomic number left to right C by increasing valence electrons right to left D by increasing electric charge right to left Chapter Assessment 4

Which element is a gas at room temperature? A neon B bromine D Which element is a gas at room temperature? A neon B bromine C magnesium D uranium Chapter Assessment 5

Nonmetals are located where on the periodic table? A top B bottom SCI 7.a A B C D Nonmetals are located where on the periodic table? A top B bottom C right side D left side CA Standards Practice 1

What are the elements with atomic numbers greater than 92 called? SCI 7.b A B C D What are the elements with atomic numbers greater than 92 called? A lanthanide series B actinide series C natural elements D synthetic elements CA Standards Practice 2

Carbon-12 and carbon-14 are two ____ of carbon. A isotopes B groups SCI 7.b A B C D Carbon-12 and carbon-14 are two ____ of carbon. A isotopes B groups C elements D ions CA Standards Practice 3

Isotopes that are radioactive have ____. A stable nuclei SCI 7.b A B C D Isotopes that are radioactive have ____. A stable nuclei B equal numbers of protons and neutrons C unstable nuclei D more protons than neutrons CA Standards Practice 4

____ is mass per unit volume of a substance. A Decay B Density SCI 7.c A B C D ____ is mass per unit volume of a substance. A Decay B Density C Hardness D Luster CA Standards Practice 5

Concepts in Motion 1

Concepts in Motion 2

Concepts in Motion 3

Image Bank

Image Bank

End of Resources