UNIT 2: ATOMS AND ELEMENTS

1. UNIT 2: ATOMS AND ELEMENTS Part 2 – Day 1 Periodic Table Trends and Comparisons Development of the Periodic Table

2. Aliens Activity Nautilus shell has a repeating pattern. Look carefully at the drawings of the ‘aliens’. Organize all the aliens into a meaningful pattern. Aliens LabCards

3. Activity: Trends in the Periodic Table • Using your text, define the following terms. Include the usual units used. • Ionization energy • Atomic mass • Density • Electronegativity • Atomic radius • Melting point

4. How to Organize… Baseball Cards: year, team, player, card number, value ($). alphabetically, mass, value, density, solid or liquid or gas Elements: when they were discovered, family, reactivity, state of matter, metal vs. non-metal, atomic mass, atomic number. Which way is CORRECT to organize the elements? Is it possible to organize the elements correctly in more than one way?

5. How to Organize Elements… Periodic Table Designs

6. Dutch Periodic Table 118 117 116 115 114 113 112 111 110 109 108 107 106 Strong, Journal of Chemical Education, Sept. 1989, page 743

7. Atomic Mass Atomic Mass Atomic Mass Name Name Name Dobereiner’s Triads Elements could be classified into groups of three, or triads. Trends in physical properties such as density, melting point, and atomic mass were observed. Johann Dobereiner ~1817 Calcium 40 Barium 137 Average 88.5 Strontium 87.6 Chlorine 35.5 Iodine 127 Average 81.3 Bromine 79.9 Sulfur 32 Tellurium 127.5 Average 79.8 Selenium 79.2 Dobereiner discovered groups of three related elements which he termed a triad. Smoot, Price, Smith, Chemistry A Modern Course 1987, page 161

8. Newland’s Law of Octaves Arranged the 62 known elements into groups of seven according to increasing atomic mass. He proposed that an eighth element would then repeat the properties of the first element in the previous group. John Newlands ~1863 Newland’s Law of Octaves 1 Li Na K 2 Be Mg 3 B Al 4 C Si 5 N P 6 O S 7 F Cl Smoot, Price, Smith, Chemistry A Modern Course 1987, page 161

9. Periodic Table 8A Alkali metals 1A Alkali earth metals He 2 H 1 Transition metals 1 1 3A 4A 5A 6A 7A 2A Boron group B 5 C 6 N 7 O 8 F 9 Ne 10 Li 3 Be 4 Nonmetals 2 2 Noble gases Si 14 P 15 S 16 Cl 17 Ar 18 Na 11 Mg 12 Al 13 3 3 8B 3B 4B 5B 6B 7B 1B 2B As 33 Se 34 Br 35 Kr 36 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 4 4 Te 52 I 53 Xe 54 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 5 5 At 85 Rn 86 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 6 6 Fr 87 Ra 88 Rf 104 Db 105 Sg 106 Bh 107 Hs 108 Mt 109 7 7 Lanthanoid Series 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 6 Solid C Actinoid Series Liquid Br 7 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 Gas H

10. Development of Periodic Table J.W. Dobereiner (1829) Law of Triads Elements could be classified into groups of three, or triads. Trends in physical properties such as density, melting point, and atomic mass were observed. J.A.R. Newlands (1864) Law of Octaves Arranged the 62 known elements into groups of seven according to increasing atomic mass. He proposed that an eighth element would then repeat the properties of the first element in the previous group. ****Lothar Meyer (1830 – 1895) Invented periodic table independently of Mendeleev his work was not published until 1870 - one year after Mendeleev's

11. You looked in the mirror this morning, and this is what you saw... Yes, it is 1870, and you are Russian Dmitri Mendeleev. For today’s activity, you will work through the same process that Menedeleev used to develop the Periodic Table.

12. Dmitri Mendeleev • Russian • Invented periodic table • Organized elements by properties • Arranged elements by atomic mass • Predicted existence of several unknown elements • Element 101 Dmitri Mendeleev

13. Mendeleev’s Periodic Table

14. ? ? ? Mendeleev’s Early Periodic Table TABELLE II GRUPPE I GRUPPE II GRUPPE III GRUPPE IV GRUPPE V GRUPPE VI GRUPPE VII GRUPPE VIII ___ ___ ___ ___ RH4 RH3 RH2 RH R2O RO R2O3 RO2 R2O5 RO3 R2O7 RO4 REIHEN 1 2 3 4 5 6 7 8 9 10 11 12 H = 1 Li = 7 Be = 9.4 B = 11 C = 12 N = 14 O = 16 F = 19 Na = 23 Mg = 24 Al = 27.3 Si = 28 P = 31 S = 32 Cl = 35.5 K = 39 Ca = 40 __ = 44 Ti = 48 V = 51 Cr = 52 Mn = 55 Fe = 56, Co = 59, Ni = 59, Cu = 63 (Cu = 63) Zn = 65 __ = 68 __ = 72 As = 75 Se = 78 Br = 80 Rb = 85 Sr = 87 ? Yt = 88 Zr = 90 Nb = 94 Mo = 96 __ = 100 Ru = 104, Rh = 104, Pd = 106, Ag = 108 (Ag = 108) Cd = 112 In = 113 Sn = 118 Sb = 122 Te = 125 J = 127 Cs = 133 Ba = 137 ? Di = 138 ? Ce = 140 __ __ __ __ __ __ __ ( __ ) __ __ __ __ __ __ __ __ ? Er = 178 ? La = 180 Ta = 182 W = 184 __ Os = 195, Ir = 197, Pt = 198, Au = 199 (Au = 199) Hg = 200 Tl= 204 Pb = 207 Bi = 208 __ __ __ __ __ Th = 231 __ U = 240 __ __ __ __ __ From Annalen der Chemie und Pharmacie, VIII, Supplementary Volume for 1872, p. 151.

15. Elements Properties are Predicted O’Connor Davis, MacNab, McClellan, CHEMISTRY Experiments and Principles1982, page 119,

16. Modern Periodic Table • Henry G.J. Moseley • Determined the atomic numbers of elements from their X-ray spectra (1914) • Arranged elements by increasing atomic number • Killed in WW I at age 28 (Battle of Gallipoli in Turkey) 1887 - 1915

17. Periodic Table of the Elements H 1 He 2 1 Li 3 Be 4 B 5 C 6 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 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 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 W 7 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

18. Metals and Nonmetals • Metals tend to lose electrons to form positive ions. • Nonmetals tend to gain electrons to form negative ions.

19. Alkali Metals • Group 1 of the periodic table: lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). •  (Note that hydrogen, although nominally also a member of Group 1, very rarely exhibits behaviour comparable to the alkali metals). •  The alkali metals provide one of the best examples of group trends in properties in the periodic table, with well characterized homologous behaviour down the group.

20. Alkali Metals • The alkali metals are not at all highly reactive and are rarely found in elemental form in nature (excpet Na and K). They also tarnish easily and have low melting points and densities. •  The alkali metals are silver-colored (cesium has a golden tinge), soft, low-density metals, which react readily with halogens to form ionic salts, and with water to form strongly alkaline (basic) hydroxides. • These elements all have one electron in their outermost shell, so the energetically preferred state of achieving a filled electron shell is to lose one electron to form a singly charged positive ion.

21. Alkaline Earth Metals • Group 2 of the periodic table: beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba) and radium (Ra). • The alkaline earth metals provide a good example of group trends in properties in the periodic table, with well-characterized homologous behaviour down the group.

22. Alkaline Earth Metals • The alkaline earth metals are silvery colored, soft, low-density metals, which react readily with halogens to form ionic salts, and with water, though not as rapidly as the alkali metals, to form strongly alkaline (basic) hydroxides. For example, where sodium and potassium react with water at room temperature, magnesium reacts only with steam and calcium with hot water. •  Beryllium is an exception: It does not react with water or steam, and its halides are covalent.

23. Alkaline Earth Metals • All the alkaline earth metals have two electrons in their outermost shell, so the energetically preferred state of achieving a filled electron shell is to lose two electrons to form doubly charged positive ions. •  The alkaline earth metals are named after their oxides, the alkaline earths. These oxides are basic (alkaline) when combined with water. "Earth" is an old term applied by early chemists to nonmetallic substances that are insoluble in water and resistant to heating--properties shared by these oxides.

24. Lanthanides • The lanthanide series comprises the 15 elements with atomic numbers 57 through 71 • The name "rare earths" is sometimes used to describe all the lanthanides • These elements are in fact fairly abundant in nature. • Most lanthanides are widely used in lasers. • These elements deflect UV and Infrared electromagnetic radiation and are commonly used in the production of sunglass lenses. • Lanthanides are shiny and silvery-white. They are relatively soft. • Many are used to make steel. • They react violently with most nonmetals.

25. Actinides • The actinides encompasses the 15 chemical elements that lie between actinium and lawrencium • All actinides are radioactive. • Only thorium and uranium occur naturally in the earth's crust • The remaining actinides were discovered in nuclear fallout, or were synthesized in particle colliders

26. Non Metals • The nonmetals are generally to: •  Hydrogen (H) • Carbon (C) • Nitrogen (N), Phosphorus (P) • Oxygen (O), Sulfur (S), Selenium (Se) • the halogens • the noble gases

27. Non Metals • Common properties considered characteristic of a nonmetal include: • poor conductors of heat and electricity when compared to metals • they form acidic oxides (whereas metals generally form basic oxides) • in solid form, they are dull and brittle, rather than metals which are lustrous, or malleable • usually have lower densities than metals • they have significantly lower melting points and boiling points than metals

28. Non Metals • Nonmetals make up most of the crust, atmosphere and oceans of the earth. Bulk tissues of living organisms are composed almost entirely of nonmetals. • Many nonmetals (hydrogen, nitrogen, oxygen, fluorine, chlorine, bromine, and iodine) are diatomic (two atoms in one molecule- O2)

29. Nobel Gases • The noble gases are the elements in group 18 of the periodic table. They are the most stable due to having the maximum number of valence electrons their outer shell can hold. Therefore, they rarely react with other elements since they are already stable. Other characteristics of the noble gases are that they all conduct electricity, fluoresce, are odorless and colorless, and are used in many conditions when a stable element is needed to maintain a safe and constant environment.

30. Nobel Gases • All of them exhibit an extremely low chemical reactivity; in fact no conventional compounds of helium or neon have yet been prepared. Xenon and krypton are known to show some reactivity in the laboratory. Recently argon compounds have also been successfully characterised. •  The noble gases have high ionization energies and small electronegativities. •  The noble gases have very weak inter-atomic forces of attraction, and consequently very low melting points and boiling points. This is why they are all monoatomic gases under normal conditions, even those with larger atomic masses than many normally solid elements.

31. Nobel Gases • One of the most commonly encountered uses of the noble gases in everyday life is in lighting. Argon is often used as a suitable safe and inert atmosphere for the inside of filament light bulbs. Some of the noble gases glow distinctive colors when used inside lighting tubes (neon lights). Helium, due to its non-reactivity (compared to flammable hydrogen) and lightness, is often used in blimps and balloons. Krypton is also used in lasers, and is used by doctors for eye surgery.

32. Periodic Table Assignment • From the handout, do the following questions: #11 – 14, 8, 9, 17