Presentation on theme: "The Periodic Table of Elements"— Presentation transcript:
1 The Periodic Table of Elements 10th Grade ChemistryMrs. Page
2 Who will memorize this song??? We shall see! Who will memorize this song??? We shall see!
3 Dmitri Mendeleev 1869 Russian Chemist Mendeleev organized the known elements based on atomic massHe predicted that the “gaps” on the periodic table were elements that had yet to be discovered
4 Periods Periods go across the table from left to right (rows) Periods go across the table from left to right (rows)Periods are labelled from 1-7Look at your Bohr model wkst – what is the pattern (trend) for each period?The period tells you how many electron orbitals an atom has!
5 Families or Groups Groups are the columns Each group or family has similar characteristicsLook at your Bohr model wkst what is the pattern for groups?The Group tells us the number of valence electrons
6 General Layout of the Periodic Table MetalsNonmetalsMetalloids
7 Properties of Metals Solid at room temperature (except Mercury ) Have Luster (shiny in appearance)Good conductors or heat and electricityMalleable (can be hammered into sheets)Ductile (can be pulled into wire)High Melting & Boiling PointsHigh Density
8 Properties of Nonmetals May be solids, liquids, or gases at room temperatureDo not conduct heat or electricity well (Poor Conductors)If solid, generally brittleLooks dullLow melting & boiling pointsLow density
9 Metalloids Share properties of both metals and non-metals Semi-conductors – insulate and conduct (used in computer chips)
11 Alkali Metals Group 1 Have 1 valence electron Oxidation number: +1 Extremely reactive metalsDo not occur freely in natureVery soft (can cut with knife)Low melting/boiling points compared to other metals (transition metals)Low densities (compared to other metals)React with water explosively!
12 Alkaline Earth Metals Group 2 Have 2 valence electrons Oxidation number: +2Very reactive (but not as much as alkali metals)Not found free in naturePresent in Earth’s crustHigh melting/boiling pointsLower densities than transition metals
13 Transition Metals Groups 3 – 12 Contain subshells so electron configuration gets “messy”Valence electrons are in multiple shellsForm multiple oxidation number depending on element (always cations)Have all the properties of metalsHigh melting/boiling pointsHigh densitiesIron, cobalt, and nickel, are the only elements known to produce a magnetic field.
14 Rare Earth ElementsPulled out of group 3 and placed at bottom of periodic table2 periods: lanthanide series and actinide seriesMany are man-made elementsVery difficult to isolate – found combined with each other
15 Boron Family Group 13 3 valence electrons If they form ions their oxidation number is +3All metals except Boron (metalloid)
16 Carbon Family Group 14 4 valence electrons Made up of 2 metals, 2 metalloids and 1 nonmetalDue to half full valence shell these atoms tend to form covalent bonds (share electrons)
17 Nitrogen Family Group 15 5 valence electrons Oxidation number: -3 Made up of 1 metals, 2 metalloids and 2 nonmetal
18 Oxygen Family Group 16 6 valence electrons Oxidation number: -2 Made up of 1 metals, 1 metalloids and 3 nonmetal
19 Halogen Family Group 17 7 valence electrons Oxidation Number: -1 Extremely reactive“Halogen” means “salt-former” these elements form salts when bonded to other elements (mostly alkali or alkaline earth metals)All are non-metalsExist in all three states of matter
20 Noble Gases Group 18 8 valence electrons (except He) Full valence shellsNOT reactiveRarely form compoundsAll gases at room temperature
21 YOU SHOULD NOW BE ABLE TO: Distinguish between periods and groupsExplain how group number and valence electrons are related (tell the number of valence electrons in each group)Explain how period number and electron shells are relatedDescribe how metallic properties change across a period and down a group (hint: where are the metals on the periodic table? Look at Carbon or Nitrogen families to determine trend down a group.)Describe the properties of metals, nonmetals, and metalloidsDetermine how reactivity changes down a group and across a periodDetermine the oxidation number of an elementDescribe the general characteristics of each family