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Chapter 20Chapter 20
Elements and Their PropertiesElements and Their Properties
Chapter 20Chapter 20
Section 1: MetalsSection 1: Metals
You will learn how to……..You will learn how to……..
Describe the properties of a typical metalDescribe the properties of a typical metal Identify the alkali metals and alkaline earth Identify the alkali metals and alkaline earth
metalsmetalsDifferentiate among three groups of Differentiate among three groups of
transition elementstransition elements
This is important because metals are a part This is important because metals are a part of your everyday life--- from electric cords of your everyday life--- from electric cords
to the cars you ride in.to the cars you ride in.
Metals on the Periodic TableMetals on the Periodic Table
On the periodic table, the On the periodic table, the metalsmetals are found are found on the on the LEFTLEFT side of the zig-zag line. side of the zig-zag line.
Properties ofProperties of MetalsMetalsConduct heat and electricityConduct heat and electricityLuster (shiny)Luster (shiny)Malleable (bendable or able to shape)Malleable (bendable or able to shape)Ductile (Drawn into wires)Ductile (Drawn into wires)Solid at room temperature (EXCEPT Solid at room temperature (EXCEPT
Mercury (Hg)= liquid)Mercury (Hg)= liquid)
MetalsMetalsMetals generally have 1-3 Metals generally have 1-3
electrons on their outer electrons on their outer energy level (valence energy level (valence electrons).electrons).
In chemical reactions, In chemical reactions, metals tend to metals tend to GIVE GIVE UPUP electrons easily electrons easily because they are close because they are close to having an empty to having an empty outer energy level.outer energy level.
Lithium
Valence electron
3 P
4N
MetalsMetals When a metal GIVES UP an electron, the atom then When a metal GIVES UP an electron, the atom then
has MORE protons than electrons and the atom is no has MORE protons than electrons and the atom is no longer neutral. The atom is MORE POSITIVE.longer neutral. The atom is MORE POSITIVE.
When a metal gives up an electron it becomes a When a metal gives up an electron it becomes a positively charged positively charged ion.ion.
Na gave up an electron to Cl. The Na atom becomes a positively charged ion because it has more protons than electrons.
Bonding in MetalsBonding in Metals
When metals give electrons to nonmetals, When metals give electrons to nonmetals, an an ionic bondionic bond is formed. is formed.
Metal (Na) + Nonmetal (Cl) = Ionic Bond (NaCl)
Types of MetalsTypes of Metals
Alkali MetalsAlkali MetalsAlkaline Earth MetalsAlkaline Earth MetalsTransition ElementsTransition Elements
Inner Transition Inner Transition ElementsElements
Alkali MetalsAlkali Metals Located in Located in GROUP 1GROUP 1 of the of the
periodic tableperiodic table MOST HIGHLY REACTIVEMOST HIGHLY REACTIVE
because they only have 1 valence because they only have 1 valence electron, so these elements are electron, so these elements are NOT found free in natureNOT found free in nature
Gives away the 1 valence electron Gives away the 1 valence electron because it is easier to LOSE 1 because it is easier to LOSE 1 versus gaining 7 electrons to versus gaining 7 electrons to complete the octet (8 electrons)complete the octet (8 electrons)
+1 ion+1 ion
Alkali MetalsAlkali Metals
Some uses of Alkali MetalsSome uses of Alkali MetalsLiving things need potassium and sodium Living things need potassium and sodium
compounds to stay healthy.compounds to stay healthy.
Doctors use lithium compounds to treat Doctors use lithium compounds to treat bipolar depressionbipolar depression
Alkaline Earth MetalsAlkaline Earth Metals Located in Located in GROUP 2GROUP 2 of the of the
periodic tableperiodic table 22ndnd MOST HIGHLY REACTIVEMOST HIGHLY REACTIVE
because they only have 2 because they only have 2 valence electron, so these valence electron, so these elements are NOT found free in elements are NOT found free in naturenature
Gives away the 2 valence Gives away the 2 valence electrons because it is easier to electrons because it is easier to LOSE 2 versus gaining 6 LOSE 2 versus gaining 6 electrons to complete the octet electrons to complete the octet (8electrons)(8electrons)
+2 ion+2 ion
Alkaline Earth MetalsAlkaline Earth Metals Some uses of Alkaline Earth Some uses of Alkaline Earth
MetalsMetals Magnesium and strontium are Magnesium and strontium are
used in are used in fireworks to used in are used in fireworks to produce the brilliant white color produce the brilliant white color and the bright red flashes.and the bright red flashes.
Calcium compounds are needed Calcium compounds are needed for life. Calcium compounds in for life. Calcium compounds in your bones helps make them your bones helps make them strong.strong.
Transition MetalsTransition MetalsLocated in Located in GROUP 3-12GROUP 3-12 of the of the
periodic tableperiodic table Iron TriadIron Triad = iron, cobalt, nickel (used to = iron, cobalt, nickel (used to
make steel and other metal mixtures)make steel and other metal mixtures)Coinage metalsCoinage metals = copper, silver, gold = copper, silver, gold
(used to make coins)(used to make coins)
Inner Transition MetalsInner Transition Metals Located at the bottom of the periodic tableLocated at the bottom of the periodic table
LanthanidesLanthanides Actinides- ALL are unstable and Actinides- ALL are unstable and radioactiveradioactive- - nucleus nucleus
breaks down and gives off particles and energybreaks down and gives off particles and energy
Chapter 20Chapter 20
Section 2: NonmetalsSection 2: Nonmetals
You will learn how to……..You will learn how to……..
Recognize hydrogen as a nonmetalRecognize hydrogen as a nonmetalCompare and contrast properties of the Compare and contrast properties of the
halogenshalogensDescribe properties and uses of the noble Describe properties and uses of the noble
gasesgases
This is important because nonmetals are not This is important because nonmetals are not only all around you, the are an essential only all around you, the are an essential
part of your body!part of your body!
Nonmetals on the Periodic TableNonmetals on the Periodic Table On the periodic table, the On the periodic table, the nonmetalsnonmetals are found on are found on
the RIGHT side of the zig-zag line. the RIGHT side of the zig-zag line. REMEMBER: HYDROGEN IS A NONMETAL!REMEMBER: HYDROGEN IS A NONMETAL!
Properties of NonmetalsProperties of Nonmetals
Poor conductors of heat and electricityPoor conductors of heat and electricity No luster (not shiny)No luster (not shiny) Not malleable (bendable)Not malleable (bendable) Not ductile (CAN NOT be drawn into wires)Not ductile (CAN NOT be drawn into wires) Usually gases OR brittle solids (EXCEPTION: Usually gases OR brittle solids (EXCEPTION:
Bromine (Br) = liquid)Bromine (Br) = liquid)
Sulfur
Oxygen
Did you know…..Did you know…..Most of your body mass is made up of Most of your body mass is made up of
nonmetalsnonmetals!! oxygen, carbon, hydrogen, and nitrogenoxygen, carbon, hydrogen, and nitrogen
Bonding in Bonding in NonmetalsNonmetals
Nonmetals tend to GAIN electrons to Nonmetals tend to GAIN electrons to become stable.become stable.
When a nonmetal gains an electron it When a nonmetal gains an electron it becomes a NEGATIVELY charged ION.becomes a NEGATIVELY charged ION.
NONMETAL + NOMETAL = COVALENT BONDINGNONMETAL + NOMETAL = COVALENT BONDING
(SHARE electrons)(SHARE electrons)
HydrogenHydrogen
Highly reactiveHighly reactive Is a nonmetal that acts like Is a nonmetal that acts like
a metala metal
Diatomic MoleculesDiatomic Molecules
Diatomic moleculeDiatomic molecule – consists of two atoms of the – consists of two atoms of the same element in a covalent bond.same element in a covalent bond.
Hi Bronclf Hi Bronclf ( ( HHI I BrBrOONNClClFF))HH22, I, I22, , BrBr22, O, O22, , NN22, Cl, Cl22, , FF22))
SHARE electrons
NonmetalsNonmetals
HalogensHalogens
Noble GasesNoble Gases
The HalogensThe Halogens
Located in group 7A (17) of the periodic Located in group 7A (17) of the periodic table table
Forms a SALT when reacts with a metal Forms a SALT when reacts with a metal (Example: NaCl)(Example: NaCl)
MOST HIGHLY reactive nonmetals MOST HIGHLY reactive nonmetals because they have 7 valence electronsbecause they have 7 valence electrons
Gains 1 electron to become stableGains 1 electron to become stable - 1 ions- 1 ions
SublimationSublimation
SublimationSublimation- SOLID - SOLID GAS GAS without forming a LIQUIDwithout forming a LIQUID
Example. Dry iceExample. Dry ice
Noble Gases on the Periodic TableNoble Gases on the Periodic Table
•Located in group 8A (18) of the periodic table
•Inert gases (Do not react)
•Outermost energy levels are full
•STABLE
Chapter 20Chapter 20
Section 3: Mixed GroupsSection 3: Mixed Groups
You will learn how to….You will learn how to…. Distinguish among metals, nonmetals, and Distinguish among metals, nonmetals, and
metalloidsmetalloids Describe the nature of allotropesDescribe the nature of allotropes Recognize the significance of differences in Recognize the significance of differences in
crystal structure in carboncrystal structure in carbon Understand the importance of synthetic Understand the importance of synthetic
elementselements
This is important because the elements in mixed This is important because the elements in mixed groups affect your life every day, because they groups affect your life every day, because they are in everything from the computer you use to are in everything from the computer you use to
the air you breathe.the air you breathe.
MetalloidsMetalloids
Elements ABOVE and BELOW the zig-zag Elements ABOVE and BELOW the zig-zag line (EXCEPTION: Aluminum (Al)line (EXCEPTION: Aluminum (Al)
Has properties of both METALS and Has properties of both METALS and NONMETALSNONMETALS
Boron GroupBoron Group
Carbon GroupCarbon Group
AllotropeAllotrope
AllotropeAllotrope- SAME element with a - SAME element with a DIFFERNET molecular structureDIFFERNET molecular structure
AllotropesAllotropes
This figure shows three allotropes of carbon.This figure shows three allotropes of carbon.
Nitrogen GroupNitrogen Group
Oxygen GroupOxygen Group