2 ObjectivesRelate an element’s valence electron structure to its position in the periodic table.Use the periodic table to classify an element as a metal, nonmetal, or metalloid.Compare the properties of metals, nonmetals, and metalloids.
3 New Vocabulary to Look for… PeriodGroupNoble gasMetalTransition elementLanthanideActinideNonmetalMetalloidsemiconductor
4 Relationship of the Periodic Table to Atomic Structure Periodic tables contain a vast array of information on the elements.You will learn to use the periodic table to gather information about the elements and group of elements we are studying.Modern periodic table is arranged according to increasing atomic number.What information does the atomic number tell us?
5 Periods and GroupsThe horizontal rows of the periodic table are called periods.The vertical columns are referred to as groups.Groups are also called families of elements.Elements in the same group have similar properties.
6 Atomic Structure of Elements Within a Period Each period starts with a group 1 element, which has 1 valence electron.As you move across a period the number of valence electrons increases. Moving from 1, 2, 13, 14, 15, 16, 17, 18.Group 1 elements have one electron at a higher energy level than the noble gas of the preceding period.
7 Atomic Structure of Elements Within a Group The number of valence electrons can be predicted using the periodic table.Group 1 has 1 valence electronGroup 2 has 2 valence electronsGroups have the second digit of valence electrons.13 has 3 valence electrons14 has 4 valence electronsFig. 3.8 p. 98
8 Noble Gases Group 18 have the periodic table. They have 8 valence electrons, except for He which only has 2Full energy levelsGenerally unreactive or inertNe, He, Ar
13 Alkaline Earth MetalsGroup 22 valence electronsBe, Mg, Ca, Ba
14 Valence Electrons-Properties Valence electrons help to determine the physical and chemical propertiesGroups have similar properties b/c they have the same number of valence electronsFig. 3.9 p. 99 Electrons in Energy Levels-Group 16
16 Physical States of the Elements The physical states of the elements are show on the periodic table on pMost elements are solids at room temperatureOnly two are liquids. What are they?A.B.All the gases except hydrogen are in the upper right corner of the table. List some.
18 Classifying Elements Elements are classified into groups MetalsNonmetalsMetalloidsMajority of elements are metalsLeft side and centerUpper right cornerAlong the boundary b/t metals and nonmetals
19 Metals Have luster Conduct heat Good conductors of electricity Most have high boiling pts.MalleableDuctileMost are solidOnly one metal is in the liquid state.
20 Metals Most are located in Groups 1-13 Transition Elements- Elements in Group 3-12 (all metals)Iron (Fe), nickel (Ni), Copper (Cu), Zinc (Zn)Some of period 7 are synthetic and radioactiveThe transition elements have a less predictable behavior and properties than the other metals
24 MetalsElements with the atomic numbers and are placed below the main tableIf they were part of the main table it would be extremely wideKnown as the inner transition elementsMany were unknown in Mendeleev’s time
26 Lanthanides First series of inner transition elements Also called rare earth elements- abundance 0.01%All have similar properties
27 Actinides Second series of inner transition elements 90-103 RadioactiveNone beyond uranium occur in natureUnpredictable-complex structures
28 Nonmetals Nonmetals are abundant in nature Oxygen and nitrogen make up 99% of our atmosphereCarbon is found in more compounds than all the other elements combined.
29 Nonmetals Don’t conduct electricity Poor conductors of heat Brittle when solidMany are gases at room temp.Solids lack lusterMelting points and boiling points are lowTable 3.5 p. 105 Properties of Metals and Nonmetals
30 Metalloids Have properties of both metals and nonmetals Located between the metals and nonmetalsSi, Ge and As are semiconductorDoes not conduct electricity as well as a metal, but does better than a nonmetalSi semiconductors made the computer revolution possible.
31 Atomic Structure of Metals, Metalloids and Nonmetals Differences occur b/c of the different arrangements of electronsNumber, arrangement of valence electrons along with how tightly they are held in the atom determines the behavior.
32 Valence electrons in Metals Loosely boundFree to move in the solid metalEasily lostFreedom of movement = conductivity
33 Valence electrons in Nonmetals and Metalloids Tightly heldNot easily lost
34 Chemical Reactions and Electrons Metals tend to lose valence electronsNonmetals tend to share or gain electrons
35 General Properties and Uses of Metals, Nonmetals and Metalloids Familiar MetalsJewelry, figurines, electrical circuitsSome Lanthanides and ActinidesCompounds of europium and ytterbium – picture tubes of TVNeodymium – high powered lasersCarbon and Some Other NonmetalsCarbon: Coal, natural gas, oil, graphite, diamondsBromine and Iodine – halogen lampsMetalloidsSilicon – electronic devicesPage
37 SemiconductorsMetalloids that do not conduct electricity as well as metals, but better than nonmetalsUsesTelevisionComputerHandheld electronic gamesCalculators
38 Semiconductors –Electrons and Electricity An electrical current is flowing electrons.Metals conduct electricity well because the electron are not tightly held by the nucleus and are therefore free to move.Copper wireAt room temperature Si is not a good conductor. Its four electrons are tightly held by the nucleus.In order to make it a good conductor it must be doped with another element.
40 Doping of SiBy adding small amounts of P to Si a good conductor is created.P has five valence electrons. This adds an extra electron which is free to move = electrical conductivity.n-type semiconductor (negatively charged)
41 Doping of Si By adding B to Si a good conductor is created B has three valence electrons. The shortage of electrons creates “holes” in which the electrons can move = electrical conductivity.p-type semiconductor (positively charged)
42 Diodes The combination of n-type and p-type semiconductors is a diode. Permits electrical flow in only one directionNegative terminal to positive terminal
43 TransistorsKey components in electrical circuits, amplifying the electrical signal.npn-junctionpnp-junction
44 ReviewWhere are the halogens, noble gases, alkali metals, alkaline earth metals, lanthanide and the actinides located? Give me an example of each?What are the characteristics of a metal, nonmetal and metalloid?How many valence electrons does Li have?