2Development of the Modern Periodic Table Antione Laviosier- 1st list of elementsJohn Newlands:arranged by increasing atomic mass, the properties repeat every 8 elements (law of octaves)Mendeleev : based on the similarity of properties and reactivities exhibited by certain elements using atomic mass; able to predict properties of unknown elementsHenri Moseley: each elements has a unique atomic number, which is how the current periodic table is organized.
3Development of the Modern Periodic Table The columns: groups/familiesThe rows: periodsGroup A elements:representative/main group elementsGroups 1,2, 13-18Blocks s & pGroup B elements:transition & inner transitionGroups 3-12Blocks d & f
43 Main Classifications of Elements: 1. Metals – shiny, smooth, solid at room temperature, good conductors of heat and electricity, ductile, malleable mostly group 1 and 2 and B (left of periodic table)Group 1 – alkali metalsGroup 2 – alkaline earth metalsGroup B are transition and inner transition (lanthanide and actinide series)
5Development of the Modern Periodic Table 2. Nonmetals: upper right side of the periodic tableUsually gases or brittle dull solids, poor conductors of heat and electricityOnly bromine is liquid at room temperatureHalogens: Group 17 & highly reactiveNoble gases: Group 18 & non-reactive3. Metalloids: border stair step – have properties of both metals and nonmetalsUsed in computer chips and solar cells
6Development of the Modern Periodic Table 1IA18VIIIA2IIA13IIIA14IVA15VA16VIA17VIIA3IIIB4IVB5VB6VIB7VIIB89VIIIB1011IB12IIBMetalsNonmetals
7Classification of the elements Valence electronsAtoms in groups have similar chemical properties because they have the same # of valence electronsRemember s,p,d &f blocks of the periodic tableB2p1I1A18VIIIA114IVA15VA16VIA17VIIA23IIIB4IVB5VB6VIB7VIIB89VIIIB1011IB12IIBH1s1Li2s1Na3s1K4s1Rb5s1Cs6s1Fr7s1Be2s2Mg3s2Ca4s2Sr5s2Ba6s2Ra7s2Sc3d1Ti3d2V3d3Cr4s13d5Mn3d5Fe3d6Co3d7Ni3d8Zn3d10Cu4s13d10C2p2N2p3O2p4F2p5Ne2p6He1s2Al3p1Ga4p1In5p1Tl6p1Si3p2Ge4p2Sn5p2Pb6p2P3p3As4p3Sb5p3Bi6p3S3p4Se4p4Te5p4Po6p4Cl3p54p55p5At6p5Ar3p6Kr4p6Xe5p6Rn6p6Y4d1La5d1Ac6d1Cd4d10Hg5d10Ag5s14d10Au6s15d10Zr4d2Hf5d2Rf6d2Nb4d3Ta5d3Db6d3Mo5s14d5W6s15d5Sg7s16d5Tc4d5Re5d5Bh6d5Ru4d6Os5d6Hs6d6Rh4d7Ir5d7Mt6d74d85d8IIA
8Periodic TrendsAtomic Radius: (atoms without charge) ½ the distance across atomDecreases left to right because of the pull from the nucleus as the outer energy level fillsIncrease top to bottom because of the additional energy level
9Periodic TrendsShielding- when levels of electrons “block” the pull of the nucleus from the outer electronsAs you go across the periodic table, shielding does not changeAs you go down a period, shielding increases b/c you have added a level
10Periodic Trends Atomic Radius Questions: Which has a large atomic radius: Li or Ne? Why?Which has a smaller atomic radius: Na or Cs? Why?
11Periodic Trends Ionic Radius Ions are atoms with a charge - #p+ do not equal #e-Remember that “stable” atoms/ions have 8 e- (octet rule)Atoms will gain, lose, or share e- to get 8Groups 1 – 14 lose an e- becoming positively charged and they get smaller (metals)Groups gain e- becoming negatively charged and they get bigger (nonmetals)Which is larger Na or Na+? Why?Which is smaller Br or Br-? Why?
12Periodic TrendsIonization energy: The energy required to remove the valence electron from an atom in the gaseous stateIncreases left to right because the electron is closer to the nucleusDecrease going down because the electron is further from the nucleus
13Periodic TrendsElectronegativity :The ability of an atom to attract e- when bondedin units of PaulingsF is most electronegative because F is smallest with the most pull from the nucleusFr is least electronegative because Fr is largest with least pull from the nucleus
14Periodic Trends Electronegativity decreases 1H3Li11Na19K37Rb55Cs87Fr4Be12Mg20Ca38Sr56Ba88Ra21Sc39Y57La89Ac22Ti40Zr72Hf104Rf23V41Nb73Ta105Db42Mo74W106Sg25Mn43Tc75Re107Bh26Fe44Ru76Os108Hs27Co45Rh77Ir109Mt28Ni46Pd78Pt110Uun111Uuu30Zn48Cd80Hg8O16S34Se52Te84Po7N15P33As51Sb83Bi6C14Si32Ge50Sn82Pb5B13Al31Ga49In81Tl9F17Cl35Br53I85At2He10Ne18Ar36Kr54Xe86Rn24Cr29Cu47Ag79Au112Uub114Uuq116Uuh118UuoElectronegativity decreasesIonization energy decreasesAtomic radius increasesElectronegativity increasesIonization energy increasesAtomic radius decreases
15Properties of the s-Block Elements Diagonal Relationships – some period 2 elements behave more like the period 3 elements in the next group than what is expected based on their position.Li behaves like MgB behaves like SiBe behaves like Al
16Properties of s-Block Elements H is in group 1 because it has 1 valence electronIt has metallic and non metallic propertiesMetal: loses an e-Non-metal: gas, increase reactivity (like halogens) gains an e-
17Properties of s-Block Elements Alkali Metals: Group 1React with water to form alkaline solutions, lose 1 valence e- becoming a 1+ ion, soft metal, highly reactive, the best conductors of heat and electricitySo reactive that they must be stored under oil
18Properties of s-Block Elements Alkaline Earth Metals: Group 2Shiny solids, harder than alkali metals, less reactive then alkali metals, lose 2 valence e- becoming a 2+ ion, good conductors of heat and electricity, react with water
19Properties of p-Block Elements Group 13: The “Boron” GroupBoron is a metalloid, the rest are metalsB, Al, Ga, In lose 3 valence e-Tl loses 1p valence e- (Ga and In can too)Group 14: The “Carbon” GroupC is a nonmetal, Si and Ge are metalloids, Sn and Pb are metals
20Properties of p-Block Elements Mineral: found in nature as solid crystalsOre:material that can be removed at a reasonable costAllotrope: forms of an element in the same physical state – solid, liquid, or gas – that have different structures and propertiesDiamond, graphite, and coal
21Properties of p-Block Elements Group 15: The “Nitrogen” GroupN and P are nonmetals and gain 3 e- to become a 3- charged ionAs and Sb are metalloidsBi is a metal and loses 3 e- to become a 3+ charged ionGroup 16: The “Oxygen” Group6 valence e-, gain 2 e- to become ions with a 2-chargeO, S, and Se are nonmetalsTe and Po are metalloids
22Properties of p-Block Elements Group 17: Halogens – “salt formers”Combine with metals to form saltsForm ions with a 1-charge by gaining 1 e-Group 18: Noble gasesColorless, un-reactive, full valence e-Homework: page 206 #39, 41, 45, 49
23Properties of the d and f-Block Elements Transition metalsElectric conductors, have luster and malleabilityLittle variation in atomic size, electronegativity, and ionization energy across a periodMore unpaired e- in d orbital, the increase in hardness and melting pointsVaried ions due to access of d orbital – all lose e-Inner TransitionLanthanide – silvery metals with increased melting pointHomework: page 206 # 57, 59-61, 69
24Properties of the d and f-Block Elements Magnetism – ability to be affected by magnetDiamagnetism – all e- are paired, substance is unaffected or slightly repelled by magnetic fieldParamagnetic – unpaired electron in the valence orbital is attracted to magnetic fieldFerromagnetism – strong attraction of substance, ions can align in direction of field and form permanent magnet