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Periodic TablePeriodic TableReview ActivityReview Activity
DefinitionDefinition
What does PERIODIC mean? A repeating pattern
Mendeleev left some spaces in his table because not all elements lined up according to atomic mass. He used info he knew about surrounding elements to PREDICT properties and masses of unknown elements.
How about that!
Mendeleev (1869)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
Moseley (c. 1914)Moseley (c. 1914)rearranged table by ...ATOMIC NUMBER
Determined atomic number of elements by determining number of protons in element
Seaborg (1944)Seaborg (1944)Rearranged Periodic Table with...Lanthanide and Actinide Series pulled out/separated from main Periodic Table
Discovered countless isotopes & 10 new elements
Information from Information from Periodic TablePeriodic Table
Atomic numberChemical symbolAtomic massChemical name
Plus countless other information, depending on the table used!
Columns of Table = Columns of Table = groupsgroups or or familiesfamilies
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 (pattern of valence electrons)
family # 1-2-13-14-15-16-17-18or IA-IIA-IIIA-IVA-VA-VIA-VIIA-VIIIA
valence e- 1-2-3-4-5-6-7-8
1 2
13
141516
17
18
GROUPS/FAMILIES GIVES GROUPS/FAMILIES GIVES # VALENCE E-# VALENCE E-
DefinitionDefinitionValence electronselectrons found in the outermost energy level
use the group number to determine number of valence electrons
Names of FamiliesNames 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 familyChalogensHalogensNoble gasesTransition metalsInner transition metals
Rows of Table = Rows of Table = periodsperiods
Properties are not alike within a period7 periods = number of energy levels in atom2 additional rows at bottom of table are Lanthanide and Actinide series and belong to periods 6 and 7
7654321
PERIOD = # ENERGY LEVELSPERIOD = # ENERGY LEVELS
TrendsTrendsValence numberCharge of ionTendency to gain or lose electronsAtomic size (radius)Ionization energyElectron affinityElectronegativityReactivityMetallic vs. nonmetallic properties
PeriodicPeriodicLawLaw
The physical and chemical properties of the elements are periodic functions of their atomic number.
The tendency of atoms to gain or lose electrons so they acquire 8 electrons in their outer energy level for stability
Octet Octet RuleRule
Ionization Ionization EnergyEnergy
energy required to remove an electron from an atom; to form a cation
kJ/mol
attraction of an atom for an added electron; to form an anion
kJ/mol
Electron Electron AffinityAffinity
Atomic Atomic RadiusRadius
estimate of the size of an atomdistance between the nucleus and the likely location of electron cloud
ability of an atom to compete with other atoms for electrons shared between themi.e. who wants them more?
Electro-Electro-negativitynegativity
Across a PeriodAcross a Periodradius decreasesionization energy increaseselectronegativity increases
b/c number of protons increases, as does number
of electrons… number of valence electrons increases… so EMF increases… so valence electrons held more tightly…
Atomic RadiusAtomic Radius
1
2
3
45 6
7 8 9 10
11
1213
1415 16 17 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 EnergyIonization 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
ElectronegativityElectronegativity
1
3
4
5
6
78
9
1112
1314
1516
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
Down a FamilyDown a Familyradius increasesionization energy decreaseselectronegativity decreases
b/cnumber of energy levels increases…so valence electrons held less tightly
b/c further away from nucleus…
Atomic RadiusAtomic RadiusFamily IA
Family IIA
1
3
11
1937
55 87
4
12
20
38 5688
0
50
100
150
200
250
300
0 10 20 30 40 50 60 70 80 90 100
ATOMIC NUMBER
Ionization EnergyIonization Energy
Family IA
Family IIA
1
3 1119 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
ElectronegativityElectronegativity
Family IA
Family IIA
1
3 1119 37 55
87
4
12
20 38 56 88
0
0.5
1
1.5
2
2.5
0 10 20 30 40 50 60 70 80 90 100
ATOMIC NUMBER
Alkaline Earth Metals LabAlkaline Earth Metals LabAn element that is highly reactive tends to gain or lose electrons very easily.A precipitate is an insoluble solid formed as a result of a chemical reaction.In this lab, magnesium formed the least number of precipitates, while barium formed the greatest number of precipitates.Why do you think reactivity increases down a family???
REGIONS OF THE TABLEREGIONS OF THE TABLE
METALS
METALLOIDS
NONMETALS
One more!
MetalsMetalsFound to LEFT of zigzag line on tableGood conductors of heat & electricityMalleable (can hammer into thin sheet without breaking)
Ductile (can pull into thin wire without breaking)
High melting & boiling pointsShiny in lusterTend to lose electrons
NonmetalsNonmetalsFound to RIGHT of zigzag line on tablePoor conductors of heat & electricityBrittle when solid (break irregularly)
Dull in lusterLow melting & boiling pointsTend to gain electrons
Metalloids aka Metalloids aka Semi-MetalsSemi-Metals
Found along both sides of zigzag line, with exception of Al and PoProperties of both metals & nonmetalsOkay conductors of heat & electricityShiny or dull
Who am I?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?1. Who am I?
Very good ability to conduct electricityNever found alone in natureWhen combined with other elements, usually give up 1 valence electronOnly one letter in symbol
4 clues4 clues
2. Who am I?2. Who am I?
More valence electrons than oxygenMore protons than calciumFewer protons than krypton
3 clues3 clues
3. Who am I?3. Who am I?
Poor conductorUsually found as a gasDo not bond well with othersSometimes found in signs outside restaurants
4 clues4 clues
4. Who am I?4. Who am I?Second lowest electronegativity of periodOne of most reactive in familyNot radioactiveAdd 50 protons and I’m now another element in my family
4 clues4 clues
5. Who am I?5. Who am I?
Usually found as a gasVery reactiveLightest element in familyOften form -1 ion
4 clues4 clues
6. Who am I?6. Who am I?
RadioactiveHighest atomic radius in familyUsually form -2 ion
3 clues3 clues
7. Who am I?7. Who am I?
Never found alone or unbonded in natureMost commonly form +2 ionSecond highest number of protons in family
3 clues3 clues
8. Who am I?8. Who am I?
All other members of family are metals
• Most abundant element in universe
2 clues2 clues
9. Who am I?9. Who am I?• Metals, nonmetals, and semi-
metals all found in family• Same number of protons as the
sum of the protons in the two elements directly above
2 clues2 clues
10. Who am I?10. Who am I?
• Highest ionization energy in family• Family contains metals, nonmetals,
and semi-metals• Can form positive or negative ion
3 clues3 clues
ThatThat’’s All Folks!s All Folks!
Once you have finished, check your answers with a
peer.