Matter Unit Learning Goal #4: Correlate atomic structure and the physical and chemical properties of an element to the position of the element on the periodic table.

The Periodic Table Dmitri Mendeleev (1834 - 1907)

Discovering the Periodic Table Ne Ar Kr Xe Po Rn Ra Eu Lu Pa Ac 1894-1918 C S Fe Cu Ag Sn Au Hg Pb Ancient Times Tc Hf Re At Fr Pm Np Pu Am Cm Bk Cf Es Fm Md No Lr 1923-1961 He Sc Ga Ge Rb Ru In Cs Tl Pr Nd Sm Gd Dy Ho Tm Yb La 1843-1886 Cr Mn Li K N O F Na B Be H Al Si Cl Ca Ti V Co Ni Se Br Sr Y Zr Nb Mo Rh Pd Cd Te I Ba Ta W Os Ir Mg Ce Tb Er Th U 1735-1843 P Zn As Sb Pt Bi Midd. -1700 Rf Db Sg Bh Hs Mt 1965- Journal of Chemical Education, Sept. 1989

Elements are arranged: Vertically into Groups Horizontally Into Periods

Why?

If you looked at one atom of every element in a group you would see…

Each atom has the same number of electrons in its outermost shell. An example…

The group 2 atoms all have 2 electrons in their outer shells Be (Beryllium) Atom Mg (Magnesium) Atom

The number of outer or “valence” electrons in an atom affects the way an atom bonds. The way an atom bonds determines many properties of the element. This is why elements within a group usually have similar properties.

If you looked at an atom from each element in a period you would see…

Each atom has the same number of electron shells. An example…

The period 4 atoms each have 4 electron containing shells 4th Shell K (Potassium) Atom Kr (Krypton) Atom Fe (Iron) Atom

Each group has distinct properties The periodic Table is divided into several groups based on the properties of different atoms.

Soft, silvery colored metals http://www.lyon.edu/webdata/Users/DMcDowell/GenChem/alkalishow.html Alkali Metals Soft, silvery colored metals Very reactive!!!

Group 1A: Alkali Metals Reaction of potassium + H2O Cutting sodium metal

http://www. youtube. com/watch http://www.youtube.com/watch?v=m55kgyApYrY&safety_mode=true&persist_safety_mode=1&safe=active

Alkali Metals reacting with water: Li (Lithium) – least reactive Na (Sodium) K (Potassium) Rb (Rubidium) Cs (Cesium) – more reactive What would you expect from Francium?!?!

Group 2A: Alkaline Earth Metals Magnesium Magnesium oxide

Alkaline Earth Metals Silvery-White Metals Fairly reactive Many are found in rocks in the earth’s crust

Transition Metals Most are good conductors of electricity Malleable (easily bent/hammered into wires or sheets)

How many things can you think of that have Transition Metals in them?

Metalloids lie on either side of the “staircase” They share properties with both metals and non-metals Si (Silicon) and Ge (Germanium) are very important “semi-conductors”

METALS Metals and Nonmetals Nonmetals Metalloids H He Li Be B C N O F 1 He 2 1 Li 3 Be 4 B 5 C 6 Nonmetals N 7 O 8 F 9 Ne 10 2 Na 11 Mg 12 Al 13 Si 14 P 15 S 16 Cl 17 Ar 18 3 K 19 Ca 20 Sc 21 Ti 22 V 23 Cr 24 Mn 25 Fe 26 Co 27 Ni 28 Cu 29 Zn 30 Ga 31 Ge 32 As 33 Se 34 Br 35 Kr 36 4 METALS Rb 37 Sr 38 Y 39 Zr 40 Nb 41 Mo 42 Tc 43 Ru 44 Rh 45 Pd 46 Ag 47 Cd 48 In 49 Sn 50 Sb 51 Te 52 I 53 Xe 54 5 Metalloids Cs 55 Ba 56 Hf 72 Ta 73 W 74 Re 75 Os 76 Ir 77 Pt 78 Au 79 Hg 80 Tl 81 Pb 82 Bi 83 Po 84 At 85 Rn 86 6 * Fr 87 Ra 88 Rf 104 Db 105 Sg 106 Bh 107 Hs 108 Mt 109 7 W La 57 Ce 58 Pr 59 Nd 60 Pm 61 Sm 62 Eu 63 Gd 64 Tb 65 Dy 66 Ho 67 Er 68 Tm 69 Yb 70 Lu 71 Ac 89 Th 90 Pa 91 U 92 Np 93 Pu 94 Am 95 Cm 96 Bk 97 Cf 98 Es 99 Fm 100 Md 101 No 102 Lr 103

What are semiconductors used in?

Nonmetals Brittle Do not conduct electricity

Halogens Most are poisonous Fairly reactive – react with alkali metals (eg) Na+ and Cl-

Chlorine Gas was used as a chemical weapon during World War I. It was used by the Germans in World War II.

Chlorine Gas The Germans were the first to use Chlorine gas at Ypres in 1915 Chlorine gas is a lung irritant The symptoms of gas poisoning are bright red lips, and a blue face People affected die a slow death by suffocation Decades later men who thought they had survived the war died from lung diseases such as Emphysema

CHLORINE

Noble Gases Unreactive Gases at room temperature

Jellyfish lamps made with noble gases artist- Eric Ehlenberger

Colors Noble Gases produce in lamp tubes: Ne (Neon): orange-red Ar (Argon): pale lavender He (Helium): pale peach Kr (Krypton): pale silver Xe (Xenon): pale, deep blue

Lanthanide Series Actinide Series

(A) Periods of the periodic table, and (B) groups of the periodic table.

ELEMENTS THAT EXIST AS DIATOMIC MOLECULES Remember: The “GENS” These elements exist as PAIRS when ALONE. Hydrogen (H2) Nitrogen (N2) Oxygen (O2) Halogens (F2, Cl2, Br2, I2) (P4 and S8)

Diatomic Elements H2 He Li Be B C N2 O2 F2 Ne Na Mg Al Si P S S Cl2 Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br2 Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I2 Xe Cs Ba La Hf Ta W Re Os Ir Pt Au Hg Tl Tl Pb Bi Po At Rn Fr Ra Ac Ce Pr Nd Pm Sm Eu Gd Tb Dy Ho Er Tm Yb Lu Th Pa U Np Pu Am Cm Bk Cf Es Fm Md No Lr

Melting Points H He Mg Symbol Melting point oC Li Be B C N O F Ne -259.2 He -269.7 1 1 Mg 650 Symbol Melting point oC Li 180.5 Be 1283 B 2027 C 4100 N -210.1 O -218.8 F -219.6 Ne -248.6 2 2 > 3000 oC 2000 - 3000 oC Na 98 Mg 650 Al 660 Si 1423 P 44.2 S 119 Cl -101 Ar -189.6 3 3 K 63.2 Ca 850 Sc 1423 Ti 1677 V 1917 Cr 1900 Mn 1244 Fe 1539 Co 1495 Ni 1455 Cu 1083 Zn 420 Ga 29.78 Ge 960 As 817 Se 217.4 Br -7.2 Kr -157.2 4 4 Rb 38.8 Sr 770 Y 1500 Zr 1852 Nb 2487 Mo 2610 Tc 2127 Ru 2427 Rh 1966 Pd 1550 Ag 961 Cd 321 In 156.2 Sn 231.9 Sb 630.5 Te 450 I 113.6 Xe -111.9 5 5 Cs 28.6 Ba 710 La 920 Hf 2222 Ta 2997 W 3380 Re 3180 Os 2727 Ir 2454 Pt 1769 Au 1063 Hg -38.9 Tl 303.6 Pb 327.4 Bi 271.3 Po 254 At Rn -71 6 6 Ralph A. Burns, Fundamentals of Chemistry , 1999, page 1999

Electronegativity A measure of the ability of an atom in a chemical compound to attract electrons   Electronegativities tend to increase across a period   Electronegativities tend to decrease down a group or remain the same

Electronegativities Period H B P As Se Ru Rh Pd Te Os Ir Pt Au Po At 2.1 B 2.0 P As Se 2.4 Ru 2.2 Rh Pd Te Os Ir Pt Au Po At 2.0 - 2.4 1 1 2A 3A 4A 5A 6A 7A Actinides: 1.3 - 1.5 Li 1.0 Ca Sc 1.3 Sr Y 1.2 Zr 1.4 Hf Mg La 1.1 Ac 1.0 - 1.4 Lanthanides: 1.1 - 1.3 * y Be 1.5 Al Si 1.8 Ti V 1.6 Cr Mn Fe Co Ni Cu 1.9 Zn 1.7 Ga Ge Nb Mo Tc Ag Cd In Sn Sb Ta W Re Hg Tl Pb Bi 1.5 - 1.9 C 2.5 S Br 2.8 I 2.5 - 2.9 N 3.0 O 3.5 F 4.0 Cl 3.0 - 4.0 2 2 Na 0.9 K 0.8 Rb Cs 0.7 Ba Fr Ra Below 1.0 3 3 3B 4B 5B 6B 7B 8B 1B 2B Period 4 4 5 5 6 6 7 Hill, Petrucci, General Chemistry An Integrated Approach 2nd Edition, page 373

Densities of Elements H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K 0.071 He 0.126 1 1 Li 0.53 Be 1.8 B 2.5 C 2.26 N 0.81 O 1.14 F 1.11 Ne 1.204 2 2 Na 0.97 Mg 1.74 Al 2.70 Si 2.4 P 1.82w S 2.07 Cl 1.557 Ar 1.402 3 3 K 0.86 Ca 1.55 Sc (2.5) Ti 4.5 V 5.96 Cr 7.1 Mn 7.4 Fe 7.86 Co 8.9 Ni 8.90 Cu 8.92 Zn 7.14 Ga 5.91 Ge 5.36 As 5,7 Se 4.7 Br 3.119 Kr 2.6 4 4 Rb 1.53 Sr 2.6 Y 5.51 Zr 6.4 Nb 8.4 Mo 10.2 Tc 11.5 Ru 12.5 Rh 12.5 Pd 12.0 Ag 10.5 Cd 8.6 In 7.3 Sn 7.3 Sb 6.7 Te 6.1 I 4.93 Xe 3.06 5 5 Cs 1.90 Ba 3.5 La 6.7 Hf 13.1 Ta 16.6 W 19.3 Re 21.4 Os 22.48 Ir 22.4 Pt 21.45 Au 19.3 Hg 13.55 Tl 11.85 Pb 11.34 Bi 9.8 Po 9.4 At --- Rn 4.4 6 6 8.0 – 11.9 g/cm3 12.0 – 17.9 g/cm3 > 18.0 g/cm3 Mg 1.74 Symbol Density in g/cm3C, for gases, in g/L W

Periodic Trends in Atomic Radius   Radius decreases across a period   Radius increases down a group

Atomic Radii = 1 Angstrom IA IIA IIIA IVA VA VIA VIIA Li Be B C N O F 1.52 1.11 1.86 1.60 2.31 1.97 2.44 2.15 2.62 2.17 0.88 0.77 0.70 0.66 0.64 1.43 1.17 1.10 1.04 0.99 1.22 1.22 1.21 1.17 1.14 1.62 1.40 1.41 1.37 1.33 1.71 1.75 1.46 Na Mg Al Si P S Cl K Ca Ga Ge As Se Br Rb Sr In Sn Sb Te I Cs Ba Tl Pb Bi = 1 Angstrom

Atomic Radii of Representative Elements (nm) 1A 2A 3A 4A 5A 6A 7A Li Be B C N O F 0.1.52 0.111 0.088 0.077 0.070 0.066 0.064 Na Mg Al Si P S Cl 0.186 0.160 0.143 0.117 0.110 0.104 0.099 K Ca Ga Ge As Se Br 0.231 0.197 0.122 0.122 0.121 0.117 0.114 Rb Sr In Sn Sb Te I 0.244 0.215 0.162 0.140 0.141 0.137 0.133 Cs Ba Tl Pb At Bi Po 0.262 0.217 0.171 0.175 0.146 0.140 0.140 LeMay Jr, Beall, Robblee, Brower, Chemistry Connections to Our Changing World , 1996, page 175

Increases for successive electrons taken from the same atom Ionization Energy - the energy required to remove an electron from an atom   Increases for successive electrons taken from the same atom   Tends to increase across a period   Tends to decrease down a group

Ionization Energies Period H He Mg Li Be B C N O F Ne Na Mg Al Si P S Group 1 18 H 1312 Symbol First Ionization Energy (kJ/mol) He 2372 1 1 Mg 738 2 13 14 15 16 17 Li 520 Be 900 B 801 C 1086 N 1402 O 1314 F 1681 Ne 2081 2 2 Na 496 Mg 738 Al 578 Si 787 P 1012 S 1000 Cl 1251 Ar 1521 3 3 3 4 5 6 7 8 9 10 11 12 Period K 419 Ca 590 Sc 633 Ti 659 V 651 Cr 653 Mn 717 Fe 762 Co 760 Ni 737 Cu 746 Zn 906 Ga 579 Ge 762 As 947 Se 941 Br 1140 Kr 1351 4 4 Rb 403 Sr 550 Y 600 Zr 640 Nb 652 Mo 684 Tc 702 Ru 710 Rh 720 Pd 804 Ag 731 Cd 868 In 558 Sn 709 Sb 834 Te 869 I 1008 Xe 1170 5 5 Cs 376 Ba 503 La 538 * Hf 659 Ta 761 W 770 Re 760 Os 839 Ir 878 Pt 868 Au 890 Hg 1007 Tl 589 Pb 716 Bi 703 Po 812 At -- Rn 1038 6 6 Fr -- Ra 509 Ac 490 y Rf -- Db -- Sg -- Bh -- Hs -- Mt -- Ds -- Uuu -- Uub -- Uut -- Uuq -- Uup -- Uuo -- 7 * Lanthanide series Ce 534 Pr 527 Nd 533 Pm 536 Sm 545 Eu 547 Gd 592 Tb 566 Dy 573 Ho 581 Er 589 Tm 597 Yb 603 Lu 523 y Actinide series Th 587 Pa 570 U 598 Np 600 Pu 585 Am 578 Cm 581 Bk 601 Cf 608 Es 619 Fm 627 Md 635 No 642 Lr --

Essential Elements Elements in organic matter H He Major minerals Li 1 He 2 Major minerals Li 3 Be 4 B 5 C 6 N 7 O 8 F 9 Ne 10 Trace elements Na 11 Mg 12 Al 13 Si 14 P 15 S 16 Cl 17 Ar 18 K 19 Ca 20 Sc 21 Ti 22 V 23 Cr 24 Mn 25 Fe 26 Co 27 Ni 28 Cu 29 Zn 30 Ga 31 Ge 32 As 33 Se 34 Br 35 Kr 36 Rb 37 Sr 38 Y 39 Zr 40 Nb 41 Mo 42 Tc 43 Ru 44 Rh 45 Pd 46 Ag 47 Cd 48 In 49 Sn 50 Sb 51 Te 52 I 53 Xe 54 Cs 55 Ba 56 La 57 Hf 72 Ta 72 W 74 Re 75 Os 76 Ir 77 Pt 78 Au 79 Hg 80 Tl 81 Pb 82 Bi 83 Po 84 At 85 Rn 86 Davis, Metcalfe, Williams, Castka, Modern Chemistry, 1999, page 748

The electron affinity is a measure of the energy change when an electron is added to a neutral atom to form a negative ion.

The End

Atomic Radii Ionic Radii = 1 Angstrom = 1 Angstrom 0.60 0.31 0.95 0.65 1.33 0.99 1.48 1.13 1.69 1.35 1.71 1.40 1.36 0.50 1.84 1.81 0.62 1.98 1.85 0.81 2.21 2.16 0.95 IA IIA IIIA IVA VA VIA VIIA = 1 Angstrom Li1+ Be2+ Na1+ Mg2+ Ba2+ Sr2+ Ca2+ K1+ Rb1+ Cs1+ Cl1- N3- O2- F1- S2- Se2- Br1- Te2- I1- Al3+ Ga3+ In3+ Tl3+ IA IIA IIIA IVA VA VIA VIIA Li Na K Rb Cs Cl S P Si Al Br Se As Ge Ga I Te Sb Sn In Tl Pb Bi Mg Ca Sr Ba Be F O N C B 1.52 1.11 1.86 1.60 2.31 1.97 2.44 2.15 2.62 2.17 0.88 0.77 0.70 0.66 0.64 1.43 1.17 1.10 1.04 0.99 1.22 1.22 1.21 1.17 1.14 1.62 1.40 1.41 1.37 1.33 1.71 1.75 1.46 = 1 Angstrom

The Atom An atom consists of a nucleus (of protons and neutrons) electrons in space about the nucleus. Electron cloud Nucleus

ATOM COMPOSITION The atom is mostly empty space protons and neutrons in the nucleus. the number of electrons is equal to the number of protons. electrons in space around the nucleus. extremely small. One teaspoon of water has 3 times as many atoms as the Atlantic Ocean has teaspoons of water.

Compounds composed of 2 or more elements in a fixed ratio properties differ from those of individual elements EX: table salt (NaCl)

Composition of molecules is given by a MOLECULAR FORMULA A MOLECULE is 2 more atoms bonded together – they may be the same element (ie diatomic molecule) or they may be different elements (ie caffeine) Composition of molecules is given by a MOLECULAR FORMULA H2O C8H10N4O2 - caffeine

Isotopes Atoms of the same element (same Z) but different mass number (A). Boron-10 (10B) has 5 p and 5 n Boron-11 (11B) has 5 p and 6 n 10B 11B

Isotopes & Their Uses Bone scans with radioactive technetium-99.

CARBON-14 – RADIOACTIVE ISOTOPE Occurs in trace amounts in the atmosphere Absorbed into living organisms The half-life of carbon-14 is approx 5700 years (when half the C-14 is converted to N-14)

Atomic Symbols sodium-23 Show the name of the element, a hyphen, and the mass number in hyphen notation sodium-23 Show the mass number and atomic number in nuclear symbol form mass number 23 Na atomic number 11

Isotopes? Which of the following represent isotopes of the same element? Which element is it? 234 X 234 X 235 X 238 X 92 93 92 92 1 2 3 4

IONS IONS are atoms or groups of atoms with a positive or negative charge. Donating an electron from an atom gives a CATION with a positive charge Accepting an electron to an atom gives an ANION with a negative charge To tell the difference between an atom and an ion, look to see if there is a charge in the superscript! Examples: Na+ Ca+2 I- O-2 Na Ca I O

Forming Cations & Anions A CATION forms when an atom loses one or more electrons. An ANION forms when an atom gains one or more electrons F + e- --> F- Mg --> Mg2+ + 2 e-

PREDICTING ION CHARGES In general metals (Mg) lose electrons ---> cations (Mg2+) nonmetals (F) gain electrons ---> anions (F-)

When an atom or molecule gain or loses an electron it becomes an ion. A cation has lost an electron and therefore has a positive charge An anion has gained an electron and therefore has a negative charge.

Charges on Common Ions -3 -2 -1 +1 +2 By losing or gaining e-, atom has same number of e-’s as nearest Group 8A atom.

Learning Check – Counting State the number of protons, neutrons, and electrons in each of these ions. 39 K+ 16O -2 41Ca +2 19 8 20 #p+ ______ ______ _______ #no ______ ______ _______ #e- ______ ______ _______

Elements with 1, 2, or 3 electrons in their outer shell tend to lose electrons to fill their outer shell and become cations. These are the metals which always tend to lose electrons. Elements with 5 to 7 electrons in their outer shell tend to gain electrons to fill their outer shell and become anions. These are the nonmetals which always tend to gain electrons. Semiconductors (metalloids) occur at the dividing line between metals and nonmetals.

EXAMPLE So the charge would be +1 What would the charge be on a sodium ion? Since sodium in in Group IA it is a metal and so would LOSE an electron You can tell how many would be lost by the group number Group 1A elements lose 1 electron So the charge would be +1 Remember an electron is negatively charged. When you lose them atom becomes positively charged… when you gain them it becomes negatively charged

Na +1 EXAMPLE It has 1…remember the group number! How would you right the symbol for the sodium CATION? Na +1 How many outer electrons does sodium have before it loses one? It has 1…remember the group number!