Periodic Table

first arranged the periodic table arranged them by atomic mass he noticed that they had similar chemical and physical properties but some elements were out of order Demtri Mendeleev

Henry Mosley Arranged the elements by atomic number modern table is arranged this way periodic law: the properties of the elements are periodic functions of their atomic number Patterns

metals non metals Periods Groups or Families horizontal rows members have the same # of principal energy levels vertical columns members have the same number of valance electrons members of the group have similar chemical properties Alkali Metals Alkaline Earth Metals Halogens Noble Gases Inner transition Transition B Si As Ge SbTe

MetalsMetalloidsNonmetals Luster ductile malleable good conductors of heat and electricity high melting and boiling pt. semi-metals touch a side of the staircase Has properties of both metals and nonmetals dull brittle solids poor conductors of heat and electricity low melting and boiling pt. B, Si, As, Ge, Sb, Te ONLY!!!

Group 1 - Alkali Metals valance electron(s) 1 +1 ion most active metals not found in nature by themselves form stable compounds can be obtained by electrolysis of fused salt. >Click Me< >Click Me Next<

Group 2 - Alkaline Earth Metals valance electrons 2+2 ion second most active metal some are not found in nature by themselves

Group 17 - Halogens valance electrons 7 most common ion -1 have all states of matter at room temp. F 2, Cl 2 gases Br 2, liquid I 2, solids are the most reactive non metals

Group 18 - Noble Gases valance electrons 8 Inert gases (non reactive) have the most stable electron configuration- 8 e in the valence shell Kr and Xe can react with fluorine-they have an oxidation number other than 0

Transition Elements many oxidation numbers valance electrons are in various energy levels --can lose electrons from more than one energy level form colored ions in solutions

Diatomic ElementsAllotropes Radioactive Liquids I 2, Br 2, Cl 2, F 2, O 2, N 2, H 2 all other elements are monatomic same element in various forms Different physical and chemical properties O 2 O 3 C- graphite diamond Br nonmetal Hg metal All elements over #82 have no stable isotopes I Bring Clay From Our New Home

Ionization Energy Electronegativity Atomic Radius Reactivity amount of energy needed to remove an electron the ability of an atom to attract an electron distance from the nucleus to the outer most energy level Periodic Trends patterns on the periodic table NOTE: Leave Room in each box. We will revisit in detail TABLE S the ability of a substance to undergo a change

Ionization Energy lower the energy -easier to remove across periods value increases move down a family (group) decrease harder to remove e-’s from non-metals - they need more to be stable; easier to remove from metals- they want to get rid of them.

Electronegativity range (4.0 is highestest) move across a period increases move down a family decreases non metals want e-’s so they will be attracted to them; metals want to get rid of e-’s so they will not be attracted to them

Atomic Radius period: decrease as you move across because increase in nuclear charge(+) group: increase as we go down because increasing number of energy levels in an atom

Reactivity metals: left and down most active metal Fr nonmetals; right and up most active non metal F >Click Me<

IE increases EN increases Radius decrease IE decreases EN decreases Radius increase Reactivity metal nonmetal

Metals Nonmetals lose electrons become positive ion ion is smaller than atom gain electrons become negative ions Ion is larger than atom Na Na+ + 1e Cl + 1e Cl- Atomic vs. Ionic Size