periodic table. elements all atoms of a specific element are alike all atoms of different elements...
TRANSCRIPT
Periodic Table
ELEMENTSAll atoms of a specific element are alikeAll atoms of different elements are different90 naturally occurringArranged on Periodic Table to show trends
Mendeleev (1869)Organized table by... Atomic mass
Thought pattern must exist between all elementsElements in columns show similar properties… Both physical and chemical!
Predicted properties of “missing” elements
Mendeleev’s Table
Moseley (c. 1914)rearranged table by ...Atomic number
determined atomic number of elements by determining number of protons in element
Moseley’s Table
Seaborg (1944)
rearranged Periodic Table with...Lanthanide and Actinide Series
pulled out/separated from main Periodic Table
discovered countless isotopes & 10 new elements
Before Seaborg
Information from Periodic Table
Atomic numberAtomic massChemical symbolChemical name
Periodic Law
The physical and chemical properties of the elements are periodic functions of their atomic number
Columns of Table = “groups” or “families”
Newer designation: 1-188 main families labeled with Roman Numeral and letter ‘A’Elements within the same family have similar but not identical propertiesElectron configuration varies periodically
Rows of Table = “periods”
Properties are not alike within a period7 periodsNumber of energy levels in atom2 additional rows at bottom of table are Lanthanide and Actinide series and belong to periods 6 and 7Seaborg's Extended Periodic Table
Names of FamiliesGroup 1 or IAGroup 2 or IIAGroup13 or IIIAGroup 14 or IVAGroup 15 or VAGroup 16 or VIAGroup 17 or VIIAGroup 18 or VIIIAGroups 3-12Lanthanide & Actinide series
Alkali metalsAlkaline Earth metalsBoron familyCarbon familyNitrogen familyOxygen familyHalogensNoble gasesTransition metalsRare Earth metals
MetalsFound to LEFT of zigzag line on tableGood conductors of heat & electricityMalleableDuctileHigh melting pointsLusterTend to lose electrons
NonmetalsFound to RIGHT of zigzag line on tablePoor conductors of heat & electricityBrittle when solidDullLow melting pointsTend to gain electrons
MetalloidsFound along both sides of zigzag lineProperties of both metals & nonmetalsOkay conductors of heat & electricityShiny or dull
TrendsValence numberCharge of ionTendency to gain or lose electronsReactivityAtomic size (radius)Metallic vs. nonmetallic propertiesIonization energyElectron affinityElectronegativity
Atomic Radius
1
2
3
45 6
7 8 9 10
11
1213
1415
1617 18
19
20
0
0.5
1
1.5
2
2.5
0 2 4 6 8 10 12 14 16 18 20 22
Atomic Number
PERIOD 2
PERIOD 3
Ionization Energy
1
2
3
45
6
78
9
10
11
1213
14
15 16
17
18
19
20
0
0.5
1
1.5
2
2.5
3
0 2 4 6 8 10 12 14 16 18 20 22
Atomic Number
PERIOD 2
PERIOD 3
Electronegativity
1
3
4
5
6
7
8
9
1112
13
1415
16
17
1920
0
0. 5
1
1. 5
2
2. 5
3
3. 5
4
4. 5
0 2 4 6 8 10 12 14 16 18 20 22
Atomic Number
PERIOD 2
PERIOD 3
Across a Periodradius decreasesionization energy increaseselectronegativity increases
b/c number of valence electrons increases… so EMF increases… so valence electrons held more tightly…
Atomic Radius
1
3
11
1937
55 87
4
12
20
3856
88
0
50
100
150
200
250
300
0 10 20 30 40 50 60 70 80 90 100
ATOMIC NUMBER
Family IA
Family IIA
Ionization Energy1
3 11
19 37 55 87
4
12
2038
56 88
0
200
400
600
800
1000
1200
1400
0 10 20 30 40 50 60 70 80 90 100
ATOMIC NUMBER
Family IA
Family IIA
Electronegativity1
3 1119 37 55
87
4
12
20 3856 88
0
0.5
1
1.5
2
2.5
0 10 20 30 40 50 60 70 80 90 100
ATOMIC N UMBER
Family IA
Family IIA
Down a Familyradius increasesionization energy decreaseselectronegativity decreases
b/cnumber of energy levels increases…so valence electrons held less tightly…
Electron Organization
Found in electron clouds - also described as energy levelsLimited space in each cloudElectrons want to be close to the nucleus because of EMFStart with by filling the lowest energy level and working their way out.Want to be in pairs.
Energy LevelsEnergy Level Maximum Number
of ElectronsLevel One 2
Level Two 8
Level Three 18
Level Four 32
Level Five 50
Level Six 72
Valence Electrons for the 8 major families
Valence Electron = An electron located on the outer most shellRoman Numeral tells number of valence electrons for all chemicals in the family.Each element wants to achieve 8 valence electrons to be stableDrawn as dot diagrams.
Electron Dot Diagram
X Always start HERE
X = Chemical Symbol = A valence electron
Octet Rule
The tendency of atoms to gain or lose electrons so they acquire eight electrons in their outer energy level
Who am I?Use the clues and a periodic table to predict the element.The number of clues is shown in the lower right corner.
1. Who am I?Very good ability to conduct electricityWhen combined with other elements, usually give up 1 valence electronOnly one letter in symbol
Potassium! (K)
3 clues
2. Who am I?More valence electrons than oxygenMore protons than calciumFewer protons than krypton
Bromine ! (Br)3 clues
3. Who am I?Poor conductorUsually found as a gasDo not bond well with others (like to be alone)Sometimes found in signs outside restaurants
Neon ! (Ne)4 clues
4. Who am I?Second largest atomic radius of periodOne of most reactive in the familyOne more proton than Rubidium
Strontium ! (Sr)
3 clues
5. Who am I?Usually found as a gasVery reactiveLightest element in familyOften form -1 ion
Fluorine! (F)4 clues
6. Who am I?RadioactiveHighest atomic radius in familyUsually form -2 ion
Polonium ! (Po)
3 clues
7. Who am I?Most commonly form +2 ionSecond highest number of protons in familySecond largest atomic radius in family
Barium! (Ba)3 clues
8. Who am I?All other members of family are metalsMost abundant element in universe
Hydrogen ! (H)2 clues
9. Who am I?Metals, nonmetals, and semi-metals all found in familySame number of protons as the sum of the protons in the two elements directly above2nd greatest atomic radius in my family
Lead ! (Pb)
3 clues
10. Who am I?Smallest atomic radius in my familyFamily contains metals, nonmetals, and semi-metalsCan form positive or negative ion (call this the “skip” family)
Carbon ! (C)
3 clues
1. Who am I?Very good ability to conduct electricityWhen combined with other elements, usually give up 1 valence electron2nd largest atomic radius in group
Cesium! (Cs)
3 clues
2. Who am I?More valence electrons than iodineFewer protons than rubidiumCan hurt Superman
Krypton (Kr)
3 clues
3. Who am I?Poor conductorUsually found as a gasDo not bond well with othersCan make your voice sound funny
Helium ! (He)
4 clues
4. Who am I?2nd lowest atomic radius in the groupHas twice as many protons as the element above itCan smell like rotten eggs
Sulfur ! (S)
3 clues
5. Who am I?Has more valence electrons than lithiumIs a metal that sits on the ‘zig-zag’ lineIs not radioactive
Aluminum! (Al)3 clues
6. Who am I?Has 5 occupied energy levelsIt is shiny and malleableHas a symbol that isn’t derived from the it’s English nameHas a atomic number less than 75I am NOT very valuable.
Tin ! (Sn)
5 clues
7. Who am I?Largest atomic radius on the periodic table
Francium (Fr)
1 clues