Focus On Physical Science by L53Kusd

VIEWS: 4 PAGES: 75

									                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


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




Periodic Table of Elements
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?
                      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.
                        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.
                     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.
                      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.
                             7.1 Organization of the Periodic Table


1.   A
2.   B
         If a substance transfers electricity
3.   C   easily, it is said to be ____.
4.   D
         A malleable
         B conductive
         C metalloid
         D ductile

                                         0%       0%   0%   0%


                                     A


                                              B


                                                       C


                                                            D
                             7.1 Organization of the Periodic Table


1.   A
2.   B
         The most reactive nonmetals are
3.   C   the ____ in Group 17.
4.   D
         A noble gases
         B halogens
         C semimetals
         D Actinide series

                                         0%       0%   0%   0%


                                     A


                                              B


                                                       C


                                                            D
                            7.1 Organization of the Periodic Table


1.   A
2.   B
         Fluorine has properties most similar
3.   C   to ____.
4.   D
         A oxygen
         B neon
         C lithium
         D chlorine

                                        0%       0%   0%   0%


                                    A


                                             B


                                                      C


                                                           D
7.2 Isotopes and Radioactivity


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




Release Energy
                           7.2 Isotopes and Radioactivity

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

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

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


1.   A
2.   B
         The process by which one element
3.   C   changes into another element is
4.   D   called ____.
         A radioactive decay
         B alpha particle decay
         C transmutation
         D transformation
                                       0%       0%   0%   0%


                                   A


                                            B


                                                     C


                                                          D
                                 7.2 Isotopes and Radioactivity


1.   A
2.   B
         How long would an 80 g sample
3.   C   of barium-131 take to decay to 5 g
4.   D   if the half-life is 12 days?
         A 12 days
         B 6 days
         C 36 days
         D 48 days
                                      0%       0%   0%   0%


                                  A


                                           B


                                                    C


                                                         D
                                7.2 Isotopes and Radioactivity


1.   A
2.   B
         Elements with atomic numbers
3.   C   higher than 92 are known as ____.
4.   D
         A synthetic elements
         B natural elements
         C metals
         D semimetals

                                     0%       0%   0%   0%


                                 A


                                          B


                                                   C


                                                        D
7.3 Physical Properties and Changes


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

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

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


1.   A
2.   B
         When water changes to ice, it is
3.   C   undergoing a ____.
4.   D
         A chemical change
         B physical change
         C radioactive decay
         D metallic change

                                          0%       0%   0%   0%


                                      A


                                               B


                                                        C


                                                             D
                              7.3 Physical Properties and Changes


1.   A
2.   B
         Which of the following is NOT a
3.   C   physical change?
4.   D
         A ice melting into water
         B sugar dissolving into
           water
         C sand and sugar mixing
         D burning a candle
                                         0%       0%   0%   0%


                                     A


                                              B


                                                       C


                                                            D
                              7.3 Physical Properties and Changes


1.   A
2.   B
         Which of the following is NOT a
3.   C   physical property?
4.   D
         A density
         B conductivity
         C hardness
         D all are physical
           properties
                                         0%       0%   0%   0%


                                     A


                                              B


                                                       C


                                                            D
Chapter Resources Menu
       Chapter Assessment
       California Standards Practice
       Concepts in Motion
       Image Bank
       Science Online
       Virtual Lab
       BrainPOP



 Click on a hyperlink to view the corresponding feature.
1.   A
2.   B
         Which is a property of metals?
3.   C   A poor conductors
4.   D
         B brittle
         C low melting point
         D luster


                                     0%       0%   0%   0%


                                 A


                                          B


                                                   C


                                                        D
1.   A
2.   B
         Which of the following is a
3.   C   noble gas?
4.   D
         A nitrogen
         B oxygen
         C argon
         D bromine

                                      0%       0%   0%   0%


                                  A


                                           B


                                                    C


                                                         D
1.   A
2.   B
         The half-life of Fermium-249 is 3
3.   C   minutes. How much of a 20 g sample
4.   D   of Fermium-249 will be left after 9
         minutes?
         A 2.5 g
         B 5g
         C 10 g
         D 9g                       0%       0%   0%   0%


                                A


                                         B


                                                  C


                                                       D
1.   A
2.   B
         Elements in a period are
3.   C   arranged ____.
4.   D
         A by increasing atomic
           number right to left
         B by increasing atomic
           number left to right
         C by increasing valence
           electrons right to left
                                         0%       0%   0%   0%
         D by increasing electric
           charge right to left      A


                                              B


                                                       C


                                                            D
1.   A
2.   B
         Which element is a gas at room
3.   C   temperature?
4.   D
         A neon
         B bromine
         C magnesium
         D uranium

                                     0%       0%   0%   0%


                                 A


                                          B


                                                   C


                                                        D
                                                       SCI 7.a


1.   A
2.   B
         Nonmetals are located where on the
3.   C   periodic table?
4.   D
         A top
         B bottom
         C right side
         D left side

                                    0%       0%   0%   0%


                                A


                                         B


                                                  C


                                                       D
                                                        SCI 7.b


1.   A
2.   B
         What are the elements with atomic
3.   C   numbers greater than 92 called?
4.   D
         A lanthanide series
         B actinide series
         C natural elements
         D synthetic elements

                                     0%       0%   0%   0%


                                 A


                                          B


                                                   C


                                                        D
                                                       SCI 7.b


1.   A
2.   B
         Carbon-12 and carbon-14 are two
3.   C   ____ of carbon.
4.   D
         A isotopes
         B groups
         C elements
         D ions

                                    0%       0%   0%   0%


                                A


                                         B


                                                  C


                                                       D
                                                         SCI 7.b


1.   A
2.   B
         Isotopes that are radioactive
3.   C   have ____.
4.   D
         A stable nuclei
         B equal numbers of
           protons and neutrons
         C unstable nuclei
         D more protons than
           neutrons                   0%       0%   0%   0%


                                  A


                                           B


                                                    C


                                                         D
                                                        SCI 7.c


1.   A
2.   B
         ____ is mass per unit volume of a
3.   C   substance.
4.   D
         A Decay
         B Density
         C Hardness
         D Luster

                                     0%       0%   0%   0%


                                 A


                                          B


                                                   C


                                                        D
Periodic Table of Elements




     Release Energy
Image Bank
Image Bank

								
To top