systematic table of elements increasing num mber of electrons increasin ng atomar mass Be B C N O F Ne hydrogen (1 electron) helium (2 electrons) lithium (3 electrons) beryllium (4 electrons) boron (5 electrons) carbon (6 electrons) nitrogen (7 electrons) oxygen (8 electrons) flourine (9 electrons) neon (10 electrons) Na sodium (11 electrons) Mg magnesium (12 electrons) ( )
periodic table of elements (groups I a to VIII a ) Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Ga Ge As Se Br Kr In Sn Sb Te I Xe Tl Pb Bi Po At Rn I a II a III a IV a V a VI a VII a VIII a
expected properties of the unknown element eka-silicium atomic mass: 72 specific gravity: 5.5 g/cm³ molar volume: 13.1 cm³/mol melting point: high temp. specific heat: 0.305 J/(gK) valences: 4 color: dark grey chemical properties: partially resistant against acids resistant against alkalic media sulfide is insoluble in water, soluble in (N 4 ) 2 S-solution the chloride is volatile and has a specific gravity of 1.9 g/cm³ actual properties of the element germanium (Ge) atomic mass: 72.59 specific gravity: 5.35 g/cm³ molar volume: 13.57 cm³/mol melting point: 947 C specific heat: 0.309 J/(gK) valences: 4 color: greyish-white chemical properties: resistant against diluted acids resistant against alkalic media sulfide is insoluble in water, soluble in (N 4 ) 2 S-solution the chloride evaporates at 84 C specific gravity: 1.8443 g/cm³
periodic table of elements (groups I a to VIII a ) Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Ga Ge As Se Br Kr In Sn Sb Te I Xe Tl Pb Bi Po At Rn I a II a III a IV a V a VI a VII a VIII a
periodic table of elements (groups I a to VIII a and groups I b to VIII b ) Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn I a II a III a IV a V a VI a VII a VIII a III b IV b V b VI b VII b VIII b I b II b + lanthanides and actinides
periodic table of elements (groups I a to VIII a and groups I b to VIII b ) Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn I a II a III a IV a V a VI a VII a VIII a III b IV b V b VI b VII b VIII b I b II b + lanthanides and actinides
alkali metals: - one single valence - easily oxidized - react violently with water - typical compounds: NaCl, K 2 O Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
earth alkali metals: - two valences - easily oxidized - may react violently with water - typical compounds: CaO, MgCl 2 Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
transition elements: - always metals - often two valences - differ strongly in reactivity - typical compounds: FeO, AgS Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
halogens: - mostly single valences - very reactive, corrosive - typical compounds: NaCl, Cl, F Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
noble gases: - gaseous at room temperature - very low reactivity - few compounds known Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
metals / non-metals Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
best electric conductors Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
semi-conductors IV-semi-conductors Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn III-V- semi-conductors II-VI- semi-conductors
inert, corrosion-resistant metals Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn
toxic elements Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi
abundant / rare elements Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi
periodic table of elements (groups I a to VIII a and groups I b to VIII b ) Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn I a II a III a IV a V a VI a VII a VIII a III b IV b V b VI b VII b VIII b I b II b + lanthanides and actinides
atomic number name symbol n = 1 n = 2 l = 0 n = 2 l = 1 n = 3 l = 0 1 hydrogen 1 2 helium 2 3 lithium 2 1 4 beryllium Be 2 2 5 boron B 2 2 1 6 carbon C 2 2 2 7 nitrogen N 2 2 3 8 oxygen O 2 2 4 9 fluorine F 2 2 5 10 neon Ne 2 2 6 11 sodium Na 2 2 6 1 12 magnesium Mg 2 2 6 2 13 aluminum Al 2 2 6 2 1 n = 3 l = 1
periodic table of elements (groups I a to VIII a and groups I b to VIII b ) Be B C N O F Ne f Ta W Re Os Ir Pt Au g Tl Pb Bi Po At Rn I a II a III a IV a V a VI a VII a VIII a III b IV b V b VI b VII b VIII b I b II b + lanthanides and actinides