Periodic Table of Elements

1. Periodic Table of Elements

2. The Periodic Table of Elements

3. Periodic  Periodic Law  Periodic Table • Something periodic occurs at regular or at least generally predictable intervals • Periodic law - physical and chemical properties of the elements are periodic functions of their atomic numbers • Periodic Table of Elements – a table of the elements, arranged by atomic number, that shows the patterns in their properties; based on the periodic law Can you think of anything that is periodic?

4. Element • A pure substance made up of one kind of atom that cannot be broken down into simpler substances by physical or chemical means • 90 occur naturally on earth • 25 were synthesized (made) by scientists Element Song http://www.privatehand.com/flash/elements.html

5. Mendeleev 1869 arranged by similarities by atoms mass Mendeleev left blanks where new elements could be placed as they were discovered The Early Table

6. Dmitri Mendeleev • In the 1860’s he devised a periodic table where the elements were ordered by their atomic masses • He did this by grouping elements together according to their similarities • Draft of Mendeleev's Periodic Table Image taken from: http://jscms.jrn.columbia.edu/cns/2006-04-18/fido-luxuriantflowinghair/mendeleev/

7. Mendeleev’s Published Periodic Table of Elements Why do you think there are question marks here? Image taken from: http://www.chemsoc.org/networks/learnnet/periodictable/post16/develop/mendeleev.htm

8. Mendeleev’s Predictions • Although Mendeleev’s Periodic Table of Elements had missing elements or “gaps,” he was able to predict the characteristics of these missing elements because of Periodic Law. “Ekasilicon” Germanium Notice how Mendeleev’s predictions (orange column) were very accurate when compared to Germanium’s actual characteristics (green column)

9. Arrangement by atomic number not mass by similar properties in columns Today’s Periodic Table

10. Henry Moseley • In 1914, his work led to a revision of the periodic table by rearranging the elements by their atomic numbers • He concluded that the number of protons in an atom is its atomic number • Sample X-ray Spectra Image taken from: http://dewey.library.upenn.edu/sceti/smith/

11. Reading the Periodic Table • Atomic Number – on the top – identifies the element • Symbol – in the middle, name below • Atomic Mass- below the symbol • Color of box tells metal, nonmetal or metalloid • Color of letter tells solid, liquid or gas

13. Using the Periodic Table • The boxes that make up the periodic table contain a significant amount of information. To understand this information, it is necessary to refer to the periodic table’s key(s) Atomic Number (Number of protons) Element Symbol (Written with a capital letter or a capital followed by a lower case if two letters ) Element Name Atomic Mass (Rounded to a whole number, equals the number of protons and neutrons) What is Oxygen’s physical state of matter? Which class does Oxygen fall into?

14. 3 regions Metals Non-metals Metalloids Regions of the Periodic Table

16. GROUPS Similarity in physical properties “family” Columns – up and down Arrangement of the Periodic Table

17. Important Features of the Periodic Table: Group (Family) • each column of elements on the periodic table How many groups (families) are on the Periodic Table Of Elements? FROM TOP TO BOTTOM OR BOTTOM TO THE TOP

18. Group (Family) Names Alkali Metals Alkaline Earth Metals Noble Gases Boron Group Nitrogen Group Carbon Group Oxygen Group Halogens Transition Metals

19. Left side Right side most likely to lose electrons Group 1 – can lose 1 Group 2 – can lose 2 Group 3 - can lose 3 gains electrons Group 17 – can gain 1 Group 16 – can gain 2 Trends in the Groups

20. GROUP 18 • Noble Gases • Do not interact with other elements

21. PERIODS Properties change in a pattern Shows a progression Rows - across Arrangement of the Periodic Table

22. Important Features of the Periodic Table:Period (Row) • each horizontal row of elements on the periodic table How many periods (rows) are on the Periodic Table Of Elements? FROM LEFT TO RIGHT OR RIGHT TO LEFT

23. Atomic Size Decreases as it goes ACROSS the periods Increases as it goes DOWN the groups Other Trends

24. Density Increases going DOWN the group ENDS of periods less dense MIDDLE of the periods is the MOST dense Other Trends

25. Metals Location • Found on the left of the zigzag line/staircase on the periodic table (exception  Hydrogen) Chemical Properties • Have few electrons in their outer energy level, thus lose electrons easily Physical Properties • ductile, good conductors, malleable, shiny, most are solid @ room temperature Image taken from: http://chemistry.about.com/od/periodictableelements/ig/Element-Photo-Gallery.--98/Sodium.htm What metal is not a solid @ room temperature?

26. Metals • Left side • Reactive Metals • Group 1- Alkali Metals - MOST reactive • Group 2 – Alkaline Metals “Earth” • Transition Metals • Groups 3-12 • Used in industries • Alloys – combination of 2 or more • Rare Earth Metals – Lanthanide Series • Section found at the bottom of the Periodic Table – only taken out so it would fit • Named because they were thought to be rare

27. http://www.youtube.com/watch?v=GFIvXVMbII0

28. - + + - - + + + + + - - - - + - - + + + + + - - + + - - - - Atoms with Few Electrons in their Outer Energy Level Notice: only 1 electron in outer level Notice: only 2 electrons in outer level

29. Non-Metals Location • Most found to the right of the zigzag line/staircase on the periodic table Chemical Properties • Most have almost full outer energy levels, thus they tend to gain electrons; some have completely full outer level Physical Properties • not ductile or malleable, not shiny, poor conductors, most are solid, but some are gas at room temperature Image taken from: http://nobel.scas.bcit.ca/resource/ptable/cl.htm Image taken from: https://www.dmr.nd.gov/ndgs/rockandmineral/sulfur.asp

30. Non-Metals • Right side • Groups 14- 18 • Group 18 – Noble Gases • Does NOT react with other elements • Group 17 – Halogens • Very reactive • “salt” group • Kills micro-organisms

31. - + + + + - - - - - - + + + + - - + + + + + + + - + + - - + + - - - - - - - Atoms with Full or Almost Full Outer Energy Level Notice: 2 electrons in outer level – FULL Notice: 6 electrons in outer level – almost full Notice: 7 electrons in outer level – almost full

32. Metalloids Location • Border the zigzag line/staircase on the periodic table Chemical Properties • Most atoms have ½ (≈) complete set of electrons in outer level Physical Properties • have properties of both metals and non-metals Image taken from: http://library.thinkquest.org/C0113863/bios.shtml Image taken from: http://library.thinkquest.org/C0113863/bios.shtml

33. Metalloids • Zig-zag area on the periodic table • Separates metals and non-metals • Semi-conductors • Example: Silicon used to make microchips • Characteristics of both metals and non-metals

34. - - - + - - - - + + + + + + + - + + + + + - + - - - - + + + + + - - - - - - Atoms with ½ (≈) Complete Outer Energy Level Notice: only 4 electrons in outer level Notice: only 3 electrons in outer level

35. Identify the Element Period 2 – Group 14  Period 5 – Group 2  Group 17 – Period 6  Group 4 – Period 7  Rutherfordium - Rf Carbon - C Strontium - Sr Astatine - At