The periodic Table of Elements
CHEMISTRY- CH 05 - NOTES THE PERIODIC TABLE OF ELEMENTS
Valence electrons: electrons in the last energy level Core electrons: all the other electrons Elements in a period- dissimilar properties but have their
valence electrons on same energy level
Elements in the same group have similar chemical properties because they have the same number of valance electrons. Main group elements, determining number of valence electrons, Lewis dot diagrams, valence electrons and groups, and electron config ( exceptions to rules….) OCTET, DUET ETC
Periodic table of elements Mendeleev Father of the PTE- published in 1869- 1 yr before Lothar Meyer When Mendeleev arranged elements according to atomic weight he noticed a repeating pattern of similar
properties EX: melting points, densities, colors, atomic weights and bonding powers
Was considered brilliant because he left spaces for undiscovered elements! http://www.youtube.com/watch?v=nsbXp64YPRQ ( 3:39)
Periodic table of elements
Henry Mosley:
discovered that an element is defined by it’s atomic number. An element’s atomic number is the same as the number of protons.
Mosley used the atomic number to arrange the elements on the periodic table. Periodic Law : properties of the elements show up periodically when the elements are arranged in increasing order of atomic number.
Purpose of the PTE: to organize information about the elements in a useful manner
http://www.youtube.com/watch?v=FGlzJcCSnK4&feature=related (9:56)
?
THREE CATAGORIES OF ELEMENTS: Metals
Non-metals Metalloids
Read pages 16-20 and complete the chart. Where on the PTE? Define: Physical properties/ Characteristics
Chemical properties/ Characteristics
Other stuff
Metalloids
Metals
Non- metals
?
Metals – elements found to the LEFT of the metalloids ( )-
More w/ metals alkali metals- soft, shiny, reacts violently with waterfound in nature in compounds– not alone Alkali Metals: Explosive reactions alkaline earth metals- harder, more dense, stronger, higher
melting point than GR1 metals, less reactive than alkali metals Transition metals- less reactive than GR1 and 2 metals, harder, more dense, higher melting points than G1 & G2- complex e’ configurations Actinide and Lanthanides belong in here too!!!
Non-metals – elements found to the right the metalloids Low
luster, bad conductors, brittle, many are gases at room temperature, some solids, … one that is liquid??? gain valence e’ to become stable Halogens/halides- salt formers Noble gases- stable, inert, un-reactive Also arranged according to “blocks” – depending on the atomic orbitals that are filled
Valence electrons: electrons in the last energy level Core electrons: all the other electrons Elements in a period- dissimilar properties but have their
valence electrons on same energy level
Elements in the same group have similar chemical properties because they have the same number of valance electrons. Main group elements, determining number of valence electrons, Lewis dot diagrams, valence electrons and groups, and electron config ( exceptions to rules….) OCTET, DUET ETC
Periodic table of elements Mendeleev Father of the PTE- published in 1869- 1 yr before Lothar Meyer When Mendeleev arranged elements according to atomic weight he noticed a repeating pattern of similar
properties EX: melting points, densities, colors, atomic weights and bonding powers
Was considered brilliant because he left spaces for undiscovered elements! http://www.youtube.com/watch?v=nsbXp64YPRQ ( 3:39)
Periodic table of elements
Henry Mosley:
discovered that an element is defined by it’s atomic number. An element’s atomic number is the same as the number of protons.
Mosley used the atomic number to arrange the elements on the periodic table. Periodic Law : properties of the elements show up periodically when the elements are arranged in increasing order of atomic number.
Purpose of the PTE: to organize information about the elements in a useful manner
http://www.youtube.com/watch?v=FGlzJcCSnK4&feature=related (9:56)
?
THREE CATAGORIES OF ELEMENTS: Metals
Non-metals Metalloids
Read pages 16-20 and complete the chart. Where on the PTE? Define: Physical properties/ Characteristics
Chemical properties/ Characteristics
Other stuff
Metalloids
Metals
Non- metals
?
Metals – elements found to the LEFT of the metalloids ( )-
More w/ metals alkali metals- soft, shiny, reacts violently with waterfound in nature in compounds– not alone Alkali Metals: Explosive reactions alkaline earth metals- harder, more dense, stronger, higher
melting point than GR1 metals, less reactive than alkali metals Transition metals- less reactive than GR1 and 2 metals, harder, more dense, higher melting points than G1 & G2- complex e’ configurations Actinide and Lanthanides belong in here too!!!
Non-metals – elements found to the right the metalloids Low
luster, bad conductors, brittle, many are gases at room temperature, some solids, … one that is liquid??? gain valence e’ to become stable Halogens/halides- salt formers Noble gases- stable, inert, un-reactive Also arranged according to “blocks” – depending on the atomic orbitals that are filled
