| A | B |
|---|
| Dobereiner | grouped elements in three by similar properties (1800) |
| Newlands (Law of Octatives) | 62 elements in groups of 8. increasing atomic mass. repetition of properties. 1st chart. not taken seriously. (1865) |
| Mendeleev | increasing atomic mass. repetition of properties. varied length. left gaps. 1st chart that we accepted. (1869) |
| Mosely | used x-rays to determined atomic number. increasing atomic number. left gaps. varied lengths. (1913) |
| Periodic Law | when elements are arranged in order of increasing atomic number, their physical and chemical properties how a periodic pattern. (properties regularly repeat.) |
| Arrangement of PT | Columns and Rows |
| Columns | groups or families, have similar chemical properties b/c they have same # of e in their outer shell |
| Rows | series or periods, have same # of energy levels |
| Physical state | 2 liquids (Br & Hg), 11 gases (H N O F Cl & nobel gases), 99 solids (the rest) |
| Metals | less than 3e in their outer shell and tends to lose them in chemical reactions. Located left of the line. |
| Properties of Metals | conducts heat or electricity, luster, ductile, malleable |
| Nonmetals | 4 or more e in their outer shell and tend to gain e in a chemical reaction. Located right of the line. |
| Metalloids | has properties of both metals and nonmetals. Located on the line except Al. |
| Representative Elements | groups 1-7 whose outer s and p sublevels are filling in |
| Nobel Gases | group 8 elements at the end of each period whose outer s and p are completely filled in |
| Transition Elements | metals whose d levels are filling in |
| Inner Transition Elements | metals whose f sublevels are filling in (Rare Earth Elements) |
| Families on PT (H is not a member of any family) | 1-alkali, 2-alkaline, 3-"Aluminum Family", 4-"Carbon Family" 5-"Nitrogen Family" 6-Calcogens 7-Halogens 8-Nobel Gases |
| 1-alkali metals | look alike, soft shiny metals, very reactive w/H2O & air (store in mineral oil), Na-salt/essential mineral/we produce it naturally, K-ess. min./bananna, Li-battereis/meds, Fr-decays rapidly, Cs-common radiosctive waste product |
| 2-alkaline earth metals | all silver grey, reactive (not as much as 1-can exist in air), Mg-flashbulbs/meds(antacids)/espen salt/light metal, Ca-milk/bones/compounds are white, Ba-heavy/helps doc. to see inside with x-rays, Sr-fireworks |
| 3-aluminum family (boron family) | top is metalloid grey rest is metal silver, Al-low density/high strenght/most common metal/found in clay/no mining/cheap/not reactive |
| 4-carbon family | C-dominate/chem~organic all living things have C in it/several pure forms (allotrope) diamond(rings), graphite(slides),fullerenes(bowl shaped)/found in 1980s/rare, Si(major compoent of sand)&Ge-semiconductor/computer chips&transistors, Sn-roofing/not tin cans, Pb-pipes/fishing weights/lead bullets/paint/radioactive sheild |
| 5-nitrogen family | most variety in properties, N-80%of air, P-several allotrops(white-explosive,red,black), As-Posion |
| 6-Calcogens | O-most abundant element-20%air/2nd most reactive on PT/allotropes O2-we breath O3-ozone, Po-man made/highly radioactive |
| 7-Halogens | Don't look alike but act alike, reactive, F-most reactive on PT/ reacts with all but He, Ne, Ar/cavity prevention, Cl-posionous, I-sublimes=solid to gas no liquid/disinfectant, At-man made |
| 8-Nobel gases | inert doesn't react/most inactive on periodic table/ top3 don't react/ bottom 3 forced to react with f/Ar+Ne-neonlights/Rn- by product when uranium decays, harmful |
| Periodic properties | Atomic + Ionic radius, Ionization energy, Electron affinity, Electronegativity |
| Atomic Radius | horizontal= big-small: more p + e so attraction is grater pulling it closerto the n making it smaller/ vertical= small-big: more e levels so farther which means less attraction less pull |
| Ionic Radius(r after e diff.) | loses e= smaller: lose an e level/gains e= bigger: repulsive force(needs space for new e. so old e. spread out to allow room |
| ionization energy (Endothermic) | e. closer to n.=high energy, harder to lose because it has a strong attraction e. farther from n.= low energy, easy to lose b/c less attraction/horizontal= small-big:more p + e so more attraction/vertical= big-small: more e. levels makes e. location farther from n. less atraction easy to lose |
| electron affinity (measures energy required) | nonmtls=exothermic: releasing energy/metals=endothermic-gains energy/end +, exo -/metals=high affinity, don't want to gain, need energy to resist/nonmtls=low affinity, wants to lose e.(so low it neg.#/ Nobel gases=high affinity, don't want to gain or lose e. |
| Electronegativity | no units, rates ability to attract e. in chem. bond/horizonal- small-big/vertical- big to small |
| Fluorine (F) | Smallest, 4.0, highly ractive, |
| Francium (Fr) | Decays rapidly, biggest, 0.0, highly reactive |
