mendeleev’s periodic table dmitri mendeleev modern russian table
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Mendeleev’s Periodic TableMendeleev’s Periodic Table
Dmitri Mendeleev
Modern Russian TableModern Russian Table
Stowe Periodic TableStowe Periodic Table
A Spiral Periodic TableA Spiral Periodic Table
““Mayan” Mayan” Periodic Periodic
TableTable
The Periodic TableThe Periodic Table
Period
Group or family
PeriodGroup or Family
Properties of MetalsProperties of Metals Metals are good conductors of heat and electricity
Metals are malleable
Metals are ductile
Metals have high tensile strength
Metals have luster
Examples of MetalsExamples of Metals
Potassium, K reacts with water and must be stored in kerosene
Zinc, Zn, is more stable than potassium
Copper, Cu, is a relatively soft metal, and a very good electrical conductor.
Mercury, Hg, is the only metal that exists as a liquid at room temperature
PropertiesProperties of Nonmetalsof Nonmetals
Carbon, the graphite in “pencil lead” is a great example of a nonmetallic element. Nonmetals are poor conductors of heat and electricity
Nonmetals tend to be brittle Many nonmetals are gases at room temperature
Examples of NonmetalsExamples of Nonmetals
Sulfur, S, was once known as “brimstone”
Microspheres of phosphorus, P, a reactive nonmetal
Graphite is not the only pure form of carbon, C. Diamond is also carbon; the color comes from impurities caught within the crystal structure
Properties of MetalloidsProperties of Metalloids
Metalloids straddle the border between metals and nonmetals on the periodic table.
They have properties of both metals and nonmetals. Metalloids are more brittle than metals, less brittle than most nonmetallic solids Metalloids are semiconductors of electricity Some metalloids possess metallic luster
Silicon, Si – A MetalloidSilicon, Si – A Metalloid
Silicon has metallic luster Silicon is brittle like a nonmetal Silicon is a semiconductor of electricity
Other metalloids include:
Boron, B Germanium, Ge Arsenic, As Antimony, Sb Tellurium, Te
Easily lose valence electron (Reducing agents) +1
Soft enough to cut with a knife
React violently with water Stored in Oil React with halogens to
form salts
The Properties of a Group: The Properties of a Group:
the Alkali Metalsthe Alkali Metals
The Properties of a Group The Properties of a Group IIA: IIA: Alkaline Earth Metals Alkaline Earth Metals
2 e- in outer shell Will lose 2 e- : +2
Group IIIA: The Boron Group IIIA: The Boron FamilyFamily
3 e- in the outer shell
B- metalloid, All other elements are metals, will form then 3+ ions
Al- 3rd most abundant element in earth’s crust, very strong in alloys, doesn’t corrode easily
Group IVA: Group IVA: Carbon FamilyCarbon Family
4 e- in outer shell
Si: 2nd most abundant in Earth’s crustSiO2 is in sand, semi conductor, silica=glass
Ge: electronic devices Sn: coats steel for “tin cans” Pb: In batteries and computer, used to be in paint and gas
Group VA: Group VA: Nitrogen Family Nitrogen Family
5 e- in outer shell N & P: NonmetalsAs & Sb are metalloidsBi: Metal
N: 79% of earth’s atmosphere, colorless, odorless and diatomic (N2 )
P: in your bones; in fertilizers, detergents, soft drinks
Group VIA: Group VIA: Oxygen FamilyOxygen Family
6 e- in outer (normally will gain 2e-; 2- charge then)
O, S, Se: NonmetalsTe: metalloidPo: metal (metalloid)
O: most abundant element on earth, colorless, odorless, diatomic (O2); extremely reactive, O3
S: unpleasant odor; added to natural gas to detect leaks; skunks, rotten eggs
The Properties of The Properties of Group VIIA: Group VIIA: The Halogens The Halogens
Contain 7 e- in outer shell
Easily gain valence electron (Oxidizing agents) -1 Can be prepared from their “salt” NaCl Cl2 NaF F2
KBr Br2
Group VIIIA: Noble GasesInert Elements
Filled Outer Energy (filled s and p’s)8e- in outer shell; chemically inactive
Half of the distance between nucli in covalently bonded diatomic molecule
"covalent atomic radii"
Periodic Trends in Atomic Radius
Radius decreases across a period Increased effective nuclear charge due to decreased shielding
Radius increases down a group Addition of principal quantum levels
Determination of Atomic Radius:Determination of Atomic Radius:
Table of Table of Atomic Atomic
RadiiRadii
Increases for successive electrons taken from the same atom
Tends to increase across a period
Electrons in the same quantum level do not shield as effectively as electrons in inner levels
Irregularities at half filled and filled sublevels due to extra repulsion of electrons paired in orbitals, making them easier to remove
Tends to decrease down a groupOuter electrons are farther from the nucleus
Ionization EnergyIonization Energy - the energy required to - the energy required to remove an electron from an atomremove an electron from an atom
Table of 1Table of 1stst Ionization Energies Ionization Energies
Ionization of MagnesiumIonization of Magnesium Mg + 738 kJ Mg+ + e-
Mg+ + 1451 kJ Mg2+ + e-
Mg2+ + 7733 kJ Mg3+ + e-
Another Way to Look at Ionization EnergyAnother Way to Look at Ionization Energy
ElectronegativityElectronegativity
The ability of an The ability of an atom in a atom in a molecule to molecule to attract shared attract shared electrons to electrons to itself.itself.
Linus Pauling 1901 - 1994
Table of Electronegativities
ElectronegativityElectronegativity
A measure of the ability of an atom in a chemical compound to attract electrons
Electronegativities tend to increase across a period
Electronegativities tend to decrease down a group or remain the same
Periodic Table of ElectronegativitiesPeriodic Table of Electronegativities
Ionic RadiiIonic Radii
Cations
Positively charged ions formed when an atom of a metal loses one or more electrons Smaller than the corresponding atom
Anions
Negatively charged ions formed when nonmetallic atoms gain one or more electrons Larger than the corresponding atom
Table Table of Ion of Ion SizesSizes
Summation of Periodic TrendsSummation of Periodic Trends