1

HHydrogen

Name: Hydrogen Symbol: H Atomic Number: 1 Atomic Mass: 1.00794 amu Melting Point: -259.14 °C (14.009985 °K, -434.45203 °F) Boiling Point: -252.87 °C (20.280005 °K, -423.166 °F)

Electron Configuration

N

H = 1s1

Hydrogen

What is Hydrogen?

Colorless, odorless gaseous chemical element. Lightest and most abundant element in the universe. Present in water and in all organic compounds. Chemically reacts with most elements. Discovered by Henry Cavendish in 1776.

pslawinski, metal-halide.net Name: Helium Symbol: He Atomic Number: 2 Atomic Mass: 4.002602 amu Melting Point: -272.0 °C (1.15 °K, -457.6 °F) Boiling Point: -268.6 °C (4.549994 °K, -451.48 °F)

N

Helium

Electron Configuration

He = 1s2

2

HeHelium

What is Helium?

Colorless, odorless gaseous nonmetallic element. Belongs to group 18 of the periodic table. Lowest boiling point of all elements and can only be solidified under pressure. Chemically inert, no known compounds. Discovered in the solar spectrum in 1868 by Lockyer.

3

LiLithium

Name: Lithium Symbol: Li Atomic Number: 3 Atomic Mass: 6.941 amu Melting Point: 180.54 °C (453.69 °K, 356.972 °F) Boiling Point: 1347.0 °C (1620.15 °K, 2456.6 °F)

N

Lithium

Electron Configuration

Li = 1s22s1

What is Lithium?

Socket silvery metal. First member of group 1 of the periodic table. Lithium salts are used in psychomedicine.

4

BeBeryllium

Name: Beryllium Symbol: Be Atomic Number: 4 Atomic Mass: 9.012182 amu Melting Point: 1278.0 °C (1551.15 °K, 2332.4 °F) Boiling Point: 2970.0 °C (3243.15 °K, 5378.0 °F)

N

Beryllium

Electron Configuration

Be = 1s22s2

What is Beryllium?

Grey metallic element of group 2 of the periodic table. Is toxic and can cause severe lung diseases and dermatitis. Shows high covalent character. It was isolated independently by F. Wohler and A.A. Bussy in 1828.

5

BBoron

Name: Boron Symbol: B Atomic Number: 5 Atomic Mass: 10.811 amu Melting Point: 2300.0 °C (2573.15 °K, 4172.0 °F) Boiling Point: 2550.0 °C (2823.15 °K, 4622.0 °F)

N

Boron

Electron Configuration

B = 1s22s22p1

What is Boron?

An element of group 13 of the periodic table. There are two allotropes, amorphous boron is a brown power, but metallic boron is black. The metallic form is hard (9.3 on Mohs' scale) and a bad conductor in room temperatures. It is never found free in nature. Boron-10 is used in nuclear reactor control rods and shields. It was discovered in 1808 by Sir Humphry Davy and by J.L. Gay-Lussac and L.J. Thenard.

6

CCarbon

Name: Carbon Symbol: C Atomic Number: 6 Atomic Mass: 12.0107 amu Melting Point: 3500.0 °C (3773.15 °K, 6332.0 °F) Boiling Point: 4827.0 °C (5100.15 °K, 8720.6 °F)

N

Carbon

Electron Configuration

C = 1s22s22p2

What is Carbon?

Carbon is a member of group 14 of the periodic table. It has three allotropic forms of it, diamonds, graphite and fullerite. Carbon-14 is commonly used in radioactive dating. Carbon occurs in all organic life and is the basis of organic chemistry. Carbon has the interesting chemical property of being able to bond with itself, and a wide variety of other elements.

7

NNitrogen

Name: Nitrogen Symbol: N Atomic Number: 7 Atomic Mass: 14.00674 amu Melting Point: -209.9 °C (63.250008 °K, -345.81998 °F) Boiling Point: -195.8 °C (77.35 °K, -320.44 °F)

N

Nitrogen

Electron Configuration

N = 1s22s22p3

Link

What is Nitrogen?

Colorless, gaseous element which belongs to group 15 of the periodic table. Constitutes ~78% of the atmosphere and is an essential part of the ecosystem. Nitrogen for industrial purposes is acquired by the fractional distillation of liquid air. Chemically inactive, reactive generally only at high temperatures or in electrical discharges. It was discovered in 1772 by D. Rutherford.

8

OOxygen

Name: Oxygen Symbol: O Atomic Number: 8 Atomic Mass: 15.9994 amu Melting Point: -218.4 °C (54.75 °K, -361.12 °F) Boiling Point: -183.0 °C (90.15 °K, -297.4 °F)

N

Oxygen

Electron Configuration

O = 1s22s22p4

What is Oxygen?

A colorless, odorless gaseous element belonging to group 16 of the periodic table. It is the most abundant element present in the earth's crust. It also makes up 20.8% of the Earth's atmosphere. For industrial purposes, it is separated from liquid air by fractional distillation. It is used in high temperature welding, and in breathing. It commonly comes in the form of Oxygen, but is found as Ozone in the upper atmosphere. It was discovered by Priestley in 1774.

9

FFluorine

Name: Fluorine Symbol: F Atomic Number: 9 Atomic Mass: 18.998404 amu Melting Point: -219.62 °C (53.53 °K, -363.316 °F) Boiling Point: -188.14 °C (85.01 °K, -306.652 °F)

N

Fluorine

Electron Configuration

F = 1s22s22p5

What is Fluorine?

A poisonous pale yellow gaseous element belonging to group 17 of the periodic table (The halogens). It is the most chemically reactive and electronegative element. It is highly dangerous, causing severe chemical burns on contact with flesh. Fluorine was identified by Scheele in 1771 and first isolated by Moissan in 1886.

pslawinski, wikipedia.org Name: Neon Symbol: Ne Atomic Number: 10 Atomic Mass: 20.1797 amu Melting Point: -248.6 °C (24.549994 °K, -415.48 °F) Boiling Point: -246.1 °C (27.049994 °K, -410.98 °F)

N

Neon

Electron Configuration

Ne = 1s22s22p6

10

NeNeon

What is Neon?

Colorless gaseous element of group 18 on the periodic table (noble gases). Neon occurs in the atmosphere, and comprises 0.0018% of the volume of the atmosphere. It has a distinct reddish glow when used in discharge tubes and neon based lamps. It forms almost no chemical compounds. Neon was discovered in 1898 by Sir William Ramsey and M.W. Travers.

Name: Sodium Symbol: Na Atomic Number: 11 Atomic Mass: 22.98977 amu Melting Point: 97.8 °C (370.95 °K, 208.04001 °F) Boiling Point: 552.9 °C (826.05005 °K, 1027.2201 °F)

N

Sodium

Electron Configuration

Na = 1s22s22p63s1

11

NaSodium

What is Sodium?

Soft silvery reactive element belonging to group 1 of the periodic table (alkali metals). It is highly reactive, oxidizing in air and reacting violently with water, forcing it to be kept under oil. It was first isolated by Humphrey Davy in 1807.

Name: Magnesium Symbol: Mg Atomic Number: 12 Atomic Mass: 24.305 amu Melting Point: 650.0 °C (923.15 °K, 1202.0 °F) Boiling Point: 1107.0 °C (1380.15 °K, 2024.6 °F)

N

Magnesium

Electron Configuration

Mg = 1s22s22p63s2

Link

12

MgMagnesium

What is Magnesium?

Silvery metallic element belonging to group 2 of the periodic table (alkaline-earth metals). It is essential for living organisms, and is used in a number of light alloys. Chemically very reactive, it forms a protective oxide coating when exposed to air and burns with an intense white flame. It also reacts with sulphur, nitrogen and the halogens. First isolated by Bussy in 1828.

Name: Aluminum Symbol: Al Atomic Number: 13 Atomic Mass: 26.981539 amu Melting Point: 660.37 °C (933.52 °K, 1220.666 °F) Boiling Point: 2467.0 °C (2740.15 °K, 4472.6 °F)

N

Aluminum

Electron Configuration

Al = 1s22s22p63s23p1

13

AlAluminum

What is Aluminum?

Silvery-white lustrous metallic element of group 3 of the periodic table. Highly reactive but protected by a thin transparent layer of the oxide which quickly forms in air. There are many alloys of aluminum, as well as a good number of industrial uses. Makes up 8.1% of the Earth's crust, by weight. Isolated in 1825 by H.C. Oersted.

Name: Silicon Symbol: Si Atomic Number: 14 Atomic Mass: 28.0855 amu Melting Point: 1410.0 °C (1683.15 °K, 2570.0 °F) Boiling Point: 2355.0 °C (2628.15 °K, 4271.0 °F)

N

Silicon

Electron Configuration

Si = 1s22s22p63s23p2

Link

14

SiSilicon

What is Silicon?

Metalloid element belonging to group 14 of the periodic table. It is the second most abundant element in the Earth's crust, making up 25.7% of it by weight. Chemically less reactive than carbon. First identified by Lavoisier in 1787 and first isolated in 1823 by Berzelius.

Name: Phosphorus Symbol: P Atomic Number: 15 Atomic Mass: 30.97376 amu Melting Point: 44.1 °C (317.25 °K, 111.38 °F) Boiling Point: 280.0 °C (553.15 °K, 536.0 °F)

N

Phosphorus

Electron Configuration

P = 1s22s22p63s23p3

15

PPhosphorus

What is Phosphorus?

Non-metallic element belonging to group 15 of the periodic table. Has a multiple allotropic forms. Essential element for living organisms. It was discovered by Brandt in 1669.

Name: Sulfur Symbol: S Atomic Number: 16 Atomic Mass: 32.066 amu Melting Point: 112.8 °C (385.95 °K, 235.04001 °F) Boiling Point: 444.6 °C (717.75 °K, 832.28 °F)

N

Sulfur

Electron Configuration

S = 1s22s22p63s23p4

16

SSulfur

What is Sulfur?

Yellow, nonmetallic element belonging to group 16 of the periodic table. It is an essential element in living organisms, needed in the amino acids cysteine and methionine, and hence in many proteins. Absorbed by plants from the soil as sulfate ion.

Name: Chlorine Symbol: Cl Atomic Number: 17 Atomic Mass: 35.4527 amu Melting Point: -100.98 °C (172.17 °K, -149.764 °F) Boiling Point: -34.6 °C (238.55 °K, -30.279997 °F)

N

Chlorine

Electron Configuration

Cl = 1s22s22p63s23p5

17

ClChlorine

What is Chlorine?

Halogen element. Poisonous greenish-yellow gas. Occurs widely in nature as sodium chloride in seawater. Reacts directly with many elements and compounds, strong oxidizing agent. Discovered by Karl Scheele in 1774. Humphrey David confirmed it as an element in 1810.

Name: Argon Symbol: Ar Atomic Number: 18 Atomic Mass: 39.948 amu Melting Point: -189.3 °C (83.85 °K, -308.74 °F) Boiling Point: -186.0 °C (87.15 °K, -302.8 °F)

N

Argon

Electron Configuration

Ar = 1s22s22p63s23p6

18

ArArgon

What is Argon?

Monatomic noble gas. Makes up 0.93% of the air. Colorless, odorless. Is inert and has no true compounds. Lord Rayleigh and Sir William Ramsey identified argon in 1894.

pslawinski, wikipedia.org

Name: Potassium Symbol: K Atomic Number: 19 Atomic Mass: 39.0983 amu Melting Point: 63.65 °C (336.8 °K, 146.57 °F) Boiling Point: 774.0 °C (1047.15 °K, 1425.2 °F)

N

Potassium

Electron Configuration

K = 1s22s22p63s23p6

4s1

Link

19

KPotassium

What is Potassium?

Soft silvery metallic element belonging to group 1 of the periodic table (alkali metals). Occurs naturally in seawater and a many minerals. Highly reactive, chemically, it resembles sodium in its behavior and compounds. Discovered by Sir Humphry Davy in 1807.

Name: Calcium Symbol: Ca Atomic Number: 20 Atomic Mass: 40.078 amu Melting Point: 839.0 °C (1112.15 °K, 1542.2 °F) Boiling Point: 1484.0 °C (1757.15 °K, 2703.2 °F)

N

Calcium

Electron Configuration

Ca = 1s22s22p63s23p6

4s2

20

CaCalcium

What is Calcium?

Soft grey metallic element belonging to group 2 of the periodic table. Used a reducing agent in the extraction of thorium, zirconium and uranium. Essential element for living organisms.

21

ScScandium

Name: Scandium Symbol: Sc Atomic Number: 21 Atomic Mass: 44.95591 amu Melting Point: 1539.0 °C (1812.15 °K, 2802.2 °F) Boiling Point: 2832.0 °C (3105.15 °K, 5129.6 °F)

N

Scandium

Electron Configuration

Sc = 1s22s22p63s23p6

4s23d1

What is Scandium?

Rare soft silvery metallic element belonging to group 3 of the periodic table. There are ten isotopes, nine of which are radioactive and have short half-lives. Predicted in 1869 by Mendeleev, isolated by Nilson in 1879.

Name: Titanium Symbol: Ti Atomic Number: 22 Atomic Mass: 47.867 amu Melting Point: 1660.0 °C (1933.15 °K, 3020.0 °F) Boiling Point: 3287.0 °C (3560.15 °K, 5948.6 °F)

N

Titanium

Electron Configuration

Ti = 1s22s22p63s23p6

4s23d2

22

TiTitanium

What is Titanium?

White metallic transition element. Occurs in numerous minerals. Used in strong, light corrosion-resistant alloys. Forms a passive oxide coating when exposed to air. First discovered by Gregor in 1789.

Name: Vanadium Symbol: V Atomic Number: 23 Atomic Mass: 50.9415 amu Melting Point: 1890.0 °C (2163.15 °K, 3434.0 °F) Boiling Point: 3380.0 °C (3653.15 °K, 6116.0 °F)

N

Vanadium

Electron Configuration

V = 1s22s22p63s23p6

4s23d3

23

VVanadium

What is Vanadium?

Soft and ductile, bright white metal. Good resistance to corrosion by alkalis, sulphuric and hydrochloric acid. It oxidizes readily about 933K. There are two naturally occurring isotopes of vanadium, and 5 radioisotopes, V-49 having the longest half-life at 337 days. Vanadium has nuclear applications, the foil is used in cladding titanium to steel, and vanadium-gallium tape is used to produce a superconductive magnet. Originally discovered by Andres Manuel del Rio of Mexico City in 1801. His discovery went unheeded, however, and in 1820, Nils Gabriel Sefstron of Sweden rediscovered it. Metallic vanadium was isolated by Henry Enfield Roscoe in 1867. The name vanadium comes from Vanadis, a goddess of Scandinavian mythology. Silvery-white metallic transition element. Vanadium is essential to ascidians. Rats and chickens are also known to require it. Metal powder is a fire hazard, and vanadium compounds should be considered highly toxic. May cause lung cancer if inhaled.

Name: Chromium Symbol: Cr Atomic Number: 24 Atomic Mass: 51.9961 amu Melting Point: 1857.0 °C (2130.15 °K, 3374.6 °F) Boiling Point: 2672.0 °C (2945.15 °K, 4841.6 °F)

Electron Configuration

Cr = 1s22s22p63s23p6

4s13d5

N

24

CrChromium

Link

What is Chromium?

Hard silvery transition element. Used in decorative electroplating. Discovered in 1797 by Vauquelin.

Chromium

Name: Manganese Symbol: Mn Atomic Number: 25 Atomic Mass: 54.93805 amu Melting Point: 1245.0 °C (1518.15 °K, 2273.0 °F) Boiling Point: 1962.0 °C (2235.15 °K, 3563.6 °F)

Electron Configuration

Mn = 1s22s22p63s23p6

4s23d5

N

25

MnManganese

What is Manganese?

Grey brittle metallic transition element. Rather electropositive, combines with some non-metals when heated. Discovered in 1774 by Scheele.

Manganese

Name: Iron Symbol: Fe Atomic Number: 26 Atomic Mass: 55.845 amu Melting Point: 1535.0 °C (1808.15 °K, 2795.0 °F) Boiling Point: 2750.0 °C (3023.15 °K, 4982.0 °F)

Electron Configuration

Fe = 1s22s22p63s23p6

4s23d6

N

26

FeIron

What is Iron?

Silvery malleable and ductile metallic transition element. Has nine isotopes and is the fourth most abundant element in the earth's crust. Required by living organisms as a trace element (used in hemoglobin in humans.) Quite reactive, oxidizes in moist air, displaces hydrogen from dilute acids and combines with nonmetallic elements.

Iron

Name: Cobalt Symbol: Co Atomic Number: 27 Atomic Mass: 58.9332 amu Melting Point: 1495.0 °C (1768.15 °K, 2723.0 °F) Boiling Point: 2870.0 °C (3143.15 °K, 5198.0 °F)

Electron Configuration

Co = 1s22s22p63s23p6

4s23d7

N

27

CoCobalt

What is Cobalt?

Light grey transition element. Some meteorites contain small amounts of metallic cobalt. Generally alloyed for use. Mammals require small amounts of cobalt salts. Cobalt-60, an artificially produced radioactive isotope of Cobalt is an important radioactive tracer and cancer-treatment agent. Discovered by G. Brandt in 1737.

Cobalt

Name: Nickel Symbol: Ni Atomic Number: 28 Atomic Mass: 58.6934 amu Melting Point: 1453.0 °C (1726.15 °K, 2647.4 °F) Boiling Point: 2732.0 °C (3005.15 °K, 4949.6 °F)

Electron Configuration

Ni = 1s22s22p63s23p6

4s23d8

N

28

NiNickel

Link

What is Nickel?

Malleable ductile silvery metallic transition element. Discovered by A.F. Cronstedt in 1751.

Nickel

Name: Copper Symbol: Cu Atomic Number: 29 Atomic Mass: 63.546 amu Melting Point: 1083.0 °C (1356.15 °K, 1981.4 °F) Boiling Point: 2567.0 °C (2840.15 °K, 4652.6 °F)

Electron Configuration

Cu = 1s22s22p63s23p6

4s13d10

N

29

CuCopper

Link

What is Copper?

Red-brown transition element. Known by the Romans as 'cuprum.' Extracted and used for thousands of years. Malleable, ductile and an excellent conductor of heat and electricity. When in moist conditions, a greenish layer forms on the outside.

Copper

Name: Zinc Symbol: Zn Atomic Number: 30 Atomic Mass: 65.39 amu Melting Point: 419.58 °C (692.73 °K, 787.24396 °F) Boiling Point: 907.0 °C (1180.15 °K, 1664.6 °F)

Electron Configuration

Zn = 1s22s22p63s23p6

4s23d10

N

30

ZnZinc

What is Zinc?

Blue-white metallic element. Occurs in multiple compounds naturally. Five stable isotopes are six radioactive isotopes have been found. Chemically a reactive metal, combines with oxygen and other non-metals, reacts with dilute acids to release hydrogen.

Zinc

Foobar, wikipedia.org Name: Gallium Symbol: Ga Atomic Number: 31 Atomic Mass: 69.723 amu Melting Point: 29.78 °C (302.93 °K, 85.604004 °F) Boiling Point: 2403.0 °C (2676.15 °K, 4357.4 °F)

N

Electron Configuration

Ga = 1s22s22p63s23p6

4s23d104p1

31

GaGallium

What is Gallium?

Soft silvery metallic element, belongs to group 13 of the periodic table. The two stable isotopes are Ga-69 and Ga-71. Eight radioactive isotopes are known, all having short half-lives. Gallium Arsenide is used as a semiconductor. Corrodes most other metals by diffusing into their lattice. First identified by Francois Lecoq de Boisbaudran in 1875.

Gallium

Name: Germanium Symbol: Ge Atomic Number: 32 Atomic Mass: 72.61 amu Melting Point: 937.4 °C (1210.55 °K, 1719.3201 °F) Boiling Point: 2830.0 °C (3103.15 °K, 5126.0 °F)

N

Electron Configuration

Ge = 1s22s22p63s23p6

4s23d104p2

32

GeGermanium

What is Germanium?

Lustrous hard metalloid element, belongs to group 14 of the periodic table. Forms a large number of organometallic compounds. Predicted by Mendeleev in 1871, it was actually found in 1886 by Winkler.

Germanium

Name: Arsenic Symbol: As Atomic Number: 33 Atomic Mass: 74.9216 amu Melting Point: 817.0 °C (1090.15 °K, 1502.6 °F) Boiling Point: 613.0 °C (886.15 °K, 1135.4 °F)

Electron Configuration

As = 1s22s22p63s23p6

4s23d104p3

N

33

AsArsenic

What is Arsenic?

Metalloid element of group 15. There are three allotropes, yellow, black, and grey. Reacts with halogens, concentrated oxidizing acids and hot alkalis. Albertus Magnus is believed to have been the first to isolate the element in 1250.

Arsenic

Name: Selenium Symbol: Se Atomic Number: 34 Atomic Mass: 78.96 amu Melting Point: 217.0 °C (490.15 °K, 422.6 °F) Boiling Point: 684.9 °C (958.05005 °K, 1264.8201 °F)

Electron Configuration

Se = 1s22s22p63s23p6

4s23d104p4

N

34

SeSelenium

What is Selenium?

Metalloid element, belongs to group 16 of the periodic table. Multiple allotropic forms exist. Chemically resembles sulfur. Discovered in 1817 by Jons J. Berzelius.

Selenium

Name: Bromine Symbol: Br Atomic Number: 35 Atomic Mass: 79.904 amu Melting Point: -7.2 °C (265.95 °K, 19.04 °F) Boiling Point: 58.78 °C (331.93 °K, 137.804 °F)

Electron Configuration

Br = 1s22s22p63s23p6

4s23d104p5

N

35

BrBromine

What is Bromine?

Halogen element. Red volatile liquid at room temperature. Its reactivity is somewhere between chlorine and iodine. Harmful to human tissue in a liquid state, the vapor irritates eyes and throat. Discovered in 1826 by Antoine Balard.

Bromine

RTC, wikipedia.org

Name: Krypton Symbol: Kr Atomic Number: 36 Atomic Mass: 83.8 amu Melting Point: -157.2 °C (115.950005 °K, -250.95999 °F) Boiling Point: -153.4 °C (119.75001 °K, -244.12 °F)

Electron Configuration

Kr = 1s22s22p63s23p6

4s23d104p6

N

36

KrKrypton

What is Krypton?

Colorless gaseous element, belongs to the noble gases. Occurs in the air, 0.0001% by volume. It can be extracted from liquid air by fractional distillation. Generally not isolated, but used with other inert gases in fluorescent lamps. Five natural isotopes, and five radioactive isotopes. Kr-85, the most stable radioactive isotope, has a half-life of 10.76 years and is produced in fission reactors. Practically inert, though known to form compounds with fluorine.

Krypton

Name: Rubidium Symbol: Rb Atomic Number: 37 Atomic Mass: 85.4678 amu Melting Point: 38.89 °C (312.04 °K, 102.002 °F) Boiling Point: 688.0 °C (961.15 °K, 1270.4 °F)

N

37

RbRubidium

What is Rubidium?

Soft silvery metallic element, belongs to group 1 of the periodic table. Rb-97, the naturally occurring isotope, is radioactive. It is highly reactive, with properties similar to other elements in group 1, like igniting spontaneously in air. Discovered spectroscopically in 1861 by W. Bunsen and G.R. Kirchoff.

Rb = [Kr]5s1

Rubidium

Name: Strontium Symbol: Sr Atomic Number: 38 Atomic Mass: 87.62 amu Melting Point: 769.0 °C (1042.15 °K, 1416.2 °F) Boiling Point: 1384.0 °C (1657.15 °K, 2523.2 °F)

N

38

SrStrontium

What is Strontium?

Soft yellowish metallic element, belongs to group 2 of the periodic table. Highly reactive chemically. Sr-90 is present in radioactive fallout and has a half-life of 28 years. Discovered in 1798 by Klaproth and Hope, isolated in 1808 by Humphry Davy.

Sr = [Kr]5s2

Strontium

Name: Yttrium Symbol: Y Atomic Number: 39 Atomic Mass: 88.90585 amu Melting Point: 1523.0 °C (1796.15 °K, 2773.4 °F) Boiling Point: 3337.0 °C (3610.15 °K, 6038.6 °F)

N

39

YYttrium

What is Yttrium?

Silvery-grey metallic element of group 3 on the periodic table. Found in uranium ores. The only natural isotope is Y-89, there are 14 other artificial isotopes. Chemically resembles the lanthanoids. Stable in the air below 400 degrees, Celsius. Discovered in 1828 by Friedrich Wohler.

Y = [Kr]5s24d1

Yttrium

Name: Zirconium Symbol: Zr Atomic Number: 40 Atomic Mass: 91.224 amu Melting Point: 1852.0 °C (2125.15 °K, 3365.6 °F) Boiling Point: 4377.0 °C (4650.15 °K, 7910.6 °F)

N

40

ZrZirconium

What is Zirconium?

Grey-white metallic transition element. Five natural isotopes and six radioactive isotopes are known. Used in nuclear reactors for a neutron absorber. Discovered in 1789 by Martin Klaproth, isolated in 1824 by Berzelius.

Zr = [Kr]5s24d2

Zirconium

Name: Niobium Symbol: Nb Atomic Number: 41 Atomic Mass: 92.90638 amu Melting Point: 2468.0 °C (2741.15 °K, 4474.4 °F) Boiling Point: 4927.0 °C (5200.15 °K, 8900.6 °F)

N

41

NbNiobium

What is Niobium?

Soft, ductile grey-blue metallic transition element. Used in special steels and in welded joints to increase strength. Combines with halogens and oxidizes in air at 200 degrees Celsius. Discovered by Charles Hatchett in 1801 and isolated by Blomstrand in 1864. Called columbium originally.

Nb = [Kr]5s14d5

Niobium

Name: Molybdenum Symbol: Mo Atomic Number: 42 Atomic Mass: 95.94 amu Melting Point: 2617.0 °C (2890.15 °K, 4742.6 °F) Boiling Point: 4612.0 °C (4885.15 °K, 8333.6 °F)

N

42

MoMolybdenum

What is Molybdenum?

Silvery-white, hard metallic transition element. It is chemically unreactive and is not affected by most acids. It oxidizes at high temperatures. There are seven natural isotopes, and four radioisotopes, Mo-93 being the most stable with a half-life of 3500 years. Molybdenum is used in almost all high-strength steels, it has nuclear applications, and is a catalyst in petroleum refining. Discovered in 1778 by Carl Welhelm Scheele of Sweden. Impure metal was prepared in 1782 by Peter Jacob Hjelm.

Mo = [Kr]5s14d5

Molybdenum

Name: Technetium Symbol: Tc Atomic Number: 43 Atomic Mass: (98.0) amu Melting Point: 2200.0 °C (2473.15 °K, 3992.0 °F) Boiling Point: 4877.0 °C (5150.15 °K, 8810.6 °F)

N

43

TcTechnetium

What is Technetium?

Radioactive metallic transition element. Can be detected in some stars and the fission products of uranium. First made by Perrier and Segre by bombarding molybdenum with deutrons, giving them Tc-97. Tc-99 is the most stable isotope with a half-life of 2.6x106 years. Sixteen isotopes are known. Organic technetium compounds are used in bone imaging. Chemical properties are intermediate between rhenium and manganese. Tc = [Kr]5s24d5

Technetium

Name: Ruthenium Symbol: Ru Atomic Number: 44 Atomic Mass: 101.07 amu Melting Point: 2250.0 °C (2523.15 °K, 4082.0 °F) Boiling Point: 3900.0 °C (4173.15 °K, 7052.0 °F)

N

44

RuRuthenium

What is Ruthenium?

Hard white metallic transition element. Found with platinum, used as a catalyst in some platinum alloys. Dissolves in fused alkalis, and is not attacked by acids. Reacts with halogens and oxygen at high temperatures. Isolated in 1844 by K.K. Klaus. Ru = [Kr]5s14d7

Ruthenium

Name: Rhodium Symbol: Rh Atomic Number: 45 Atomic Mass: 102.9055 amu Melting Point: 1966.0 °C (2239.15 °K, 3570.8 °F) Boiling Point: 3727.0 °C (4000.15 °K, 6740.6 °F)

N

45

RhRhodium

What is Rhodium?

Silvery white metallic transition element. Found with platinum and used in some platinum alloys. Not attacked by acids, dissolves only in aqua regia. Discovered in 1803 by W.H. Wollaston. Rh = [Kr]5s14d8

Rhodium

Name: Palladium Symbol: Pd Atomic Number: 46 Atomic Mass: 106.42 amu Melting Point: 1552.0 °C (1825.15 °K, 2825.6 °F) Boiling Point: 2927.0 °C (3200.15 °K, 5300.6 °F)

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46

PdPalladium

What is Palladium?

Soft white ductile transition element. Found with some copper and nickel ores. Does not react with oxygen at normal temperatures. Dissolves slowly in hydrochloric acid. Discovered in 1803 by W.H. Wollaston. Pd = [Kr]4d10

Palladium

Name: Silver Symbol: Ag Atomic Number: 47 Atomic Mass: 107.8682 amu Melting Point: 961.93 °C (1235.08 °K, 1763.474 °F) Boiling Point: 2212.0 °C (2485.15 °K, 4013.6 °F)

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AgSilver

What is Silver?

White lustrous soft metallic transition element. Found in both its elemental form and in minerals. Used in jewelry, tableware and so on. Less reactive than silver, chemically.

Ag = [Kr]5s14d10

Silver

Name: Cadmium Symbol: Cd Atomic Number: 48 Atomic Mass: 112.411 amu Melting Point: 320.9 °C (594.05 °K, 609.62 °F) Boiling Point: 765.0 °C (1038.15 °K, 1409.0 °F)

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48

CdCadmium

What is Cadmium?

Soft bluish metal belonging to group 12 of the periodic table. Extremely toxic even in low concentrations. Chemically similar to zinc, but lends itself to more complex compounds. Discovered in 1817 by F. Stromeyer.

Cd = [Kr]5s24d10

Cadmium

Name: Indium Symbol: In Atomic Number: 49 Atomic Mass: 114.818 amu Melting Point: 156.61 °C (429.76 °K, 313.898 °F) Boiling Point: 2000.0 °C (2273.15 °K, 3632.0 °F)

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49

InIndium

What is Indium?

Soft silvery element belonging to group 13 of the periodic table. The most common natural isotope is In-115, which has a half-life of 6x104 years. Five other radioisotopes exist. Discovered in 1863 by Reich and Richter.

In = [Kr]5s24d105p1

Indium

Name: Tin Symbol: Sn Atomic Number: 50 Atomic Mass: 118.71 amu Melting Point: 231.9 °C (505.05 °K, 449.41998 °F) Boiling Point: 2270.0 °C (2543.15 °K, 4118.0 °F)

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50

SnTin

What is Tin?

Silvery malleable metallic element belonging to group 14 of the periodic table. Twenty-six isotopes are known, five of which are radioactive. Chemically reactive. Combines directly with chlorine and oxygen and displaces hydrogen from dilute acids. Sn = [Kr]5s24d105p2

Tin

Name: Antimony Symbol: Sb Atomic Number: 51 Atomic Mass: 121.76 amu Melting Point: 630.0 °C (903.15 °K, 1166.0 °F) Boiling Point: 1750.0 °C (2023.15 °K, 3182.0 °F)

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51

SbAntimony

What is Antimony?

Element of group 15. Multiple allotropic forms. The stable form of antimony is a blue-white metal. Yellow and black antimony are unstable non-metals. Used in flame-proofing, paints, ceramics, enamels, and rubber. Attacked by oxidizing acids and halogens. First reported by Tholden in 1450.

Sb = [Kr]5s24d105p3

Antimony

Name: Tellurium Symbol: Te Atomic Number: 52 Atomic Mass: 127.6 amu Melting Point: 449.5 °C (722.65 °K, 841.1 °F) Boiling Point: 989.8 °C (1262.95 °K, 1813.64 °F)

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52

TeTellurium

What is Tellurium?

Silvery metalloid element of group 16. Eight natural isotopes, nine radioactive isotopes. Used in semiconductors and to a degree in some steels. Chemistry is similar to sulfur. Discovered in 1782 by Franz Miller.

Te = [Kr]5s24d105p4

Tellurium

Name: Iodine Symbol: I Atomic Number: 53 Atomic Mass: 126.90447 amu Melting Point: 113.5 °C (386.65 °K, 236.3 °F) Boiling Point: 184.0 °C (457.15 °K, 363.2 °F)

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53

IIodine

What is Iodine?

Dark violet nonmetallic element, belongs to group 17 of the periodic table. Insoluble in water. Required as a trace element for living organisms. One stable isotope, I-127 exists, in addition to fourteen radioactive isotopes. Chemically the least reactive of the halogens, and the most electropositive metallic halogen. Discovered in 1812 by Courtois.

I = [Kr]5s24d105p5

Iodine

Name: Xenon Symbol: Xe Atomic Number: 54 Atomic Mass: 131.29 amu Melting Point: -111.9 °C (161.25 °K, -169.42 °F) Boiling Point: -108.1 °C (165.05 °K, -162.58 °F)

54

XeXenon

What is Xenon?

Colorless, odorless gas belonging to group 18 on the periodic table (the noble gases.) Nine natural isotopes and seven radioactive isotopes are known. Xenon was part of the first noble-gas compound synthesized. Several others involving Xenon have been found since then. Xenon was discovered by Ramsey and Travers in 1898.

Xe = [Kr]5s24d105p6

Xenon

pslawinski, wikipedia.org

Name: Cesium Symbol: Cs Atomic Number: 55 Atomic Mass: 132.90546 amu Melting Point: 28.5 °C (301.65 °K, 83.3 °F) Boiling Point: 678.4 °C (951.55005 °K, 1253.12 °F)

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55

CsCesium

What is Cesium?

Soft silvery-white metallic element belonging to group 1 of the periodic table. One of the three metals which are liquid at room temperature. Cs-133 is the natural, and only stable, isotope. Fifteen other radioisotopes exist. Cesium reacts explosively with cold water, and ice at temperatures above 15 K. Cesium hydroxide is the strongest base known.

Cs = [Xe]6s1

Cesium

Name: Barium Symbol: Ba Atomic Number: 56 Atomic Mass: 137.327 amu Melting Point: 725.0 °C (998.15 °K, 1337.0 °F) Boiling Point: 1140.0 °C (1413.15 °K, 2084.0 °F)

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56

BaBarium

What is Barium?

Silvery-white reactive element, belonging to group 2 of the periodic table. Soluble barium compounds are extremely poisonous. Identified in 1774 by Karl Scheele and extracted in 1808 by Humphry Davy.

Ba = [Xe]6s2

Barium

57

LaLanthanum

Name: Lanthanum Symbol: La Atomic Number: 57 Atomic Mass: 138.9055 amu Melting Point: 920.0 °C (1193.15 °K, 1688.0 °F) Boiling Point: 3469.0 °C (3742.15 °K, 6276.2 °F)

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What is Lanthanum?

(From the Greek word lanthanein, to line hidden) Silvery metallic element belonging to group 3 of the periodic table and oft considered to be one of the lanthanoids. Found in some rare-earth minerals. Twenty-five natural isotopes exist. La-139 which is stable, and La-138 which has a half-life of 1010 to 1015 years. The other twenty-three isotopes are radioactive. It resembles the lanthanoids chemically. Lanthanum has a low to moderate level of toxicity, and should be handled with care. Discovered in 1839 by C.G. Mosander.

La = [Xe]5d16s2

Lanthanum

Name: Cerium Symbol: Ce Atomic Number: 58 Atomic Mass: 140.116 amu Melting Point: 795.0 °C (1068.15 °K, 1463.0 °F) Boiling Point: 3257.0 °C (3530.15 °K, 5894.6 °F)

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58

CeCerium

What is Cerium?

Silvery metallic element, belongs to the lanthanoids. Four natural isotopes exist, and fifteen radioactive isotopes have been identified. Used in some rare-earth alloys. The oxidized form is used in the glass industry. Discovered by Martin .H. Klaproth in 1803.

Ce = [Xe] 6s24f15d1

Cerium

Name: Praseodymium Symbol: Pr Atomic Number: 59 Atomic Mass: 140.90765 amu Melting Point: 935.0 °C (1208.15 °K, 1715.0 °F) Boiling Point: 3127.0 °C (3400.15 °K, 5660.6 °F)

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59

PrPraseodymium

What is Praseodymium?

Soft silvery metallic element, belongs to the lanthanoids. Only natural isotope is Pr-141 which is not radioactive. Fourteen radioactive isotopes have been artificially produced. Used in rare-earth alloys. Discovered in 1885 by C.A. von Welsbach.

Pr = [Xe] 6s24f3

Praseodymium

Name: Neodymium Symbol: Nd Atomic Number: 60 Atomic Mass: 144.24 amu Melting Point: 1010.0 °C (1283.15 °K, 1850.0 °F) Boiling Point: 3127.0 °C (3400.15 °K, 5660.6 °F)

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60

NdNeodymium

What is Neodymium?

Soft bright silvery metallic element, belongs to the lanthanoids. Seven natural isotopes, Nd-144 being the only radioactive one with a half-life of 1010 to 1015 years. Six artificial radioisotopes have been produced. The metal is used in glass works to color class a shade of violet-purple and make it dichroic. One of the more reactive rare-earth metals, quickly reacts with air. Used in some rare-earth alloys. Neodymium is used to color the glass used in welder's glasses. Neodymium is also used in very powerful, permanent magnets (Nd2Fe14B). Discovered by Carl F. Auer von Welsbach in Austria in 1885 by separating didymium into its elemental components praseodymium and neodymium.

Nd = [Xe] 6s24f4

Neodymium

Name: Promethium Symbol: Pm Atomic Number: 61 Atomic Mass: (145.0) amu Melting Point: Unknown Boiling Point: Unknown

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61

PmPromethium

What is Promethium?

Soft silvery metallic element, belongs to the lanthanoids. Pm-147, the only natural isotope, is radioactive and has a half-life of 252 years. Eighteen radioisotopes have been produced, but all have very short half-lives. Found only in nuclear decay waste. Pm-147 is of interest as a beta-decay source, however Pm-146 and Pm-148 have to be removed from it first, as they generate gamma radiation. Discovered by J.A. Marinsky, L.E. Glendenin and C.D. Coryell in 1947.

Pm = [Xe] 6s24f5

Promethium

Name: Samarium Symbol: Sm Atomic Number: 62 Atomic Mass: 150.36 amu Melting Point: 1072.0 °C (1345.15 °K, 1961.6 °F) Boiling Point: 1900.0 °C (2173.15 °K, 3452.0 °F)

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62

SmSamarium

What is Samarium?

Soft silvery metallic element, belongs to the lanthanoids. Seven natural isotopes, Sm-147 is the only radioisotope, and has a half-life of 2.5x1011 years. Used for making special alloys needed in the production of nuclear reactors. Also used as a neutron absorber. Small quantities of samarium oxide is used in special optical glasses. The largest use of the element is its ferromagnetic alloy which produces permanent magnets that are five times stronger than magnets produced by any other material. Discovered by Francois Lecoq de Boisbaudran in 1879.

Sm = [Xe] 6s24f6

Samarium

Name: Europium Symbol: Eu Atomic Number: 63 Atomic Mass: 151.964 amu Melting Point: 822.0 °C (1095.15 °K, 1511.6 °F) Boiling Point: 1597.0 °C (1870.15 °K, 2906.6 °F)

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EuEuropium

What is Europium?

Soft silvery metallic element belonging to the lanthanoids. Eu-151 and Eu-153 are the only two stable isotopes, both of which are neutron absorbers. Discovered in 1889 by Sir William Crookes. Eu = [Xe] 6s24f7

Europium

Name: Gadolinium Symbol: Gd Atomic Number: 64 Atomic Mass: 157.25 amu Melting Point: 1311.0 °C (1584.15 °K, 2391.8 °F) Boiling Point: 3233.0 °C (3506.15 °K, 5851.4 °F)

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64

GdGadolinium

What is Gadolinium?

Soft silvery metallic element belonging to the lanthanoids. Seven natural, stable isotopes are known in addition to eleven artificial isotopes. Gd-155 and Gd-157 and the best neutron absorbers of all elements. Gadolinium compounds are used in electronics. Discovered by J.C.G Marignac in 1880.

Gd = [Xe] 6s25d14f7

Gadolinium

Name: Terbium Symbol: Tb Atomic Number: 65 Atomic Mass: 158.92534 amu Melting Point: 1360.0 °C (1633.15 °K, 2480.0 °F) Boiling Point: 3041.0 °C (3314.15 °K, 5505.8 °F)

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65

TbTerbium

What is Terbium?

Silvery metallic element belonging to the lanthanoids. Tb-159 is the only stable isotope, there are seventeen artificial isotopes. Discovered by G.G. Mosander in 1843. Tb = [Xe] 6s24f9

Terbium

Name: Dysprosium Symbol: Dy Atomic Number: 66 Atomic Mass: 162.5 amu Melting Point: 1412.0 °C (1685.15 °K, 2573.6 °F) Boiling Point: 2562.0 °C (2835.15 °K, 4643.6 °F)

66

DyDysprosium

What is Dysprosium?

Metallic with a bright silvery-white luster. Dysprosium belongs to the lanthanoids. It is relatively stable in air at room temperatures, it will however dissolve in mineral acids, evolving hydrogen. It is found in from rare-earth minerals. There are seven natural isotopes of dysprosium, and eight radioisotopes, Dy-154 being the most stable with a half-life of 3x106 years. Dysprosium is used as a neutron absorber in nuclear fission reactions, and in compact disks. It was discovered by Paul Emile Lecoq de Boisbaudran in 1886 in France. Its name comes from the Greek word dysprositos, which means hard to obtain.

Dy = [Xe] 6s24f10

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Dysprosium

Name: Holmium Symbol: Ho Atomic Number: 67 Atomic Mass: 164.93031 amu Melting Point: 1470.0 °C (1743.15 °K, 2678.0 °F) Boiling Point: 2720.0 °C (2993.15 °K, 4928.0 °F)

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HoHolmium

What is Holmium?

Relatively soft and malleable silvery-white metallic element, which is stable in dry air at room temperature. It oxidizes in moist air and at high temperatures. It belongs to the lanthanoids. A rare-earth metal, it is found in the minerals monazite and gadolinite. It possesses unusual magnetic properties. One natural isotope, Ho-165 exists, six radioisotopes exist, the most stable being Ho-163 with a half-life of 4570 years. Holmium is used in some metal alloys, it is also said to stimulate the metabolism. Discovered by Per Theodor Cleve and J.L. Soret in Switzerland in 1879. The name homium comes from the Greek word Holmia which means Sweden. While all holmium compounds should be considered highly toxic, initial evidence seems to indicate that they do not pose much danger. The metal's dust however, is a fire hazard.

Holmium

Name: Erbium Symbol: Er Atomic Number: 68 Atomic Mass: 167.26 amu Melting Point: 1522.0 °C (1795.15 °K, 2771.6 °F) Boiling Point: 2510.0 °C (2783.15 °K, 4550.0 °F)

68

ErErbium

What is Erbium?

Soft silvery metallic element which belongs to the lanthanoids. Six natural isotopes that are stable. Twelve artificial isotopes are known. Used in nuclear technology as a neutron absorber. It is being investigated for other possible uses. Discovered by Carl G. Mosander in 1843.

Erbium

Name: Thulium Symbol: Tm Atomic Number: 69 Atomic Mass: 168.9342 amu Melting Point: 1545.0 °C (1818.15 °K, 2813.0 °F) Boiling Point: 1727.0 °C (2000.15 °K, 3140.6 °F)

69

TmThulium

What is Thulium?

Soft grey metallic element that belongs to the lanthanoids. One natural isotope exists, Tm-169, and seventeen artificial isotopes have been produced. No known uses for the element. Discovered in 1879 by Per Theodor Cleve.

Thulium

Name: Ytterbium Symbol: Yb Atomic Number: 70 Atomic Mass: 173.04 amu Melting Point: 824.0 °C (1097.15 °K, 1515.2 °F) Boiling Point: 1466.0 °C (1739.15 °K, 2670.8 °F)

70

YbYtterbium

What is Ytterbium?

Silvery metallic element of the lanthanoids. Seven natural isotopes and ten artificial isotopes are known. Used in certain steels. Discovered by J.D.G. Marignac in 1878.

Ytterbium

Name: Lutetium Symbol: Lu Atomic Number: 71 Atomic Mass: 174.967 amu Melting Point: 1656.0 °C (1929.15 °K, 3012.8 °F) Boiling Point: 3315.0 °C (3588.15 °K, 5999.0 °F)

71

LuLutetium

What is Lutetium?

Silvery-white rare-earth metal which is relatively stable in air. It happens to be the most expensive rare-earth metal. Its found with almost all rare-earth metals, but is very difficult to separate from other elements. Least abundant of all natural elements. Used in metal alloys, and as a catalyst in various processes. There are two natural, stable isotopes, and seven radioisotopes, the most stable being Lu-174 with a half-life of 3.3 years. The separation of lutetium from ytterbium was described by Georges Urbain in 1907. It was discovered at approximately the same time by Carl Auer von Welsbach. The name comes from the Greek word lutetia which means Paris.

Lutetium

Name: Hafnium Symbol: Hf Atomic Number: 72 Atomic Mass: 178.49 amu Melting Point: 2150.0 °C (2423.15 °K, 3902.0 °F) Boiling Point: 5400.0 °C (5673.15 °K, 9752.0 °F)

72

HfHafnium

What is Hafnium?

Silvery lustrous metallic transition element. Used in tungsten alloys in filaments and electrodes, also acts as a neutron absorber. First reported by Urbain in 1911, existence was finally established in 1923 by D. Coster, G.C. de Hevesy in 1923.

Hafnium

Name: Tantalum Symbol: Ta Atomic Number: 73 Atomic Mass: 180.9479 amu Melting Point: 2996.0 °C (3269.15 °K, 5424.8 °F) Boiling Point: 5425.0 °C (5698.15 °K, 9797.0 °F)

73

TaTantalum

What is Tantalum?

Heavy blue-grey metallic transition element. Ta-181 is a stable isotope, and Ta-180 is a radioactive isotope, with a half-life in excess of 10^7 years. Used in surgery as it is unreactive. Forms a passive oxide layer in air. Identified in 1802 by Ekeberg and isolated in 1820 by Jons J. Berzelius.

Tantalum

Name: Tungsten Symbol: W Atomic Number: 74 Atomic Mass: 183.84 amu Melting Point: 3410.0 °C (3683.15 °K, 6170.0 °F) Boiling Point: 5660.0 °C (5933.15 °K, 10220.0 °F)

74

WTungsten

What is Tungsten?

White or grey metallic transition element, formerly called wolfram. Forms a protective oxide in air and can be oxidized at high temperature. First isolated by Jose and Fausto de Elhuyer in 1783.

Tungsten

Name: Rhenium Symbol: Re Atomic Number: 75 Atomic Mass: 186.207 amu Melting Point: 3180.0 °C (3453.15 °K, 5756.0 °F) Boiling Point: 5627.0 °C (5900.15 °K, 10160.6 °F)

75

ReRhenium

What is Rhenium?

Silvery-white metallic transition element. Obtained as a by-product of molybdenum refinement. Rhenium-molybdenum alloys are superconducting.

Rhenium

Name: Osmium Symbol: Os Atomic Number: 76 Atomic Mass: 190.23 amu Melting Point: 3045.0 °C (3318.15 °K, 5513.0 °F) Boiling Point: 5027.0 °C (5300.15 °K, 9080.6 °F)

76

OsOsmium

What is Osmium?

Hard blue-white metallic transition element. Found with platinum and used in some alloys with platinum and iridium.

Osmium

Name: Iridium Symbol: Ir Atomic Number: 77 Atomic Mass: 192.217 amu Melting Point: 2410.0 °C (2683.15 °K, 4370.0 °F) Boiling Point: 4527.0 °C (4800.15 °K, 8180.6 °F)

77

IrIridium

What is Iridium?

Very hard and brittle, silvery metallic transition element. It has a yellowish cast to it. Salts of iridium are highly colored. It is the most corrosion resistant metal known, not attacked by any acid, but is attacked by molten salts. There are two natural isotopes of iridium, and 4 radioisotopes, the most stable being Ir-192 with a half-life of 73.83 days. Ir-192 decays into platinum, while the other radioisotopes decay into osmium. Iridium is used in high temperature apparatus, electrical contacts, and as a hardening agent for platinum. Discovered in 1803 by Smithson Tennant in England. The name comes from the Greek word iris, which means rainbow. Iridium metal is generally non-toxic due to its relative unreactivity, but iridium compounds should be considered highly toxic.

Iridium

Name: Platinum Symbol: Pt Atomic Number: 78 Atomic Mass: 195.078 amu Melting Point: 1772.0 °C (2045.15 °K, 3221.6 °F) Boiling Point: 3827.0 °C (4100.15 °K, 6920.6 °F)

78

PtPlatinum

What is Platinum?

Attractive greyish-white metal. When pure, it is malleable and ductile. Does not oxidize in air, insoluble in hydrochloric and nitric acid. Corroded by halogens, cyandies, sulphur and alkalis. Hydrogen and oxygen react explosively in the presence of platinum. There are six stable isotopes and three radioisotopes, the most stable being Pt-193 with a half-life of 60 years. Platinum is used in jewelry, laboratory equipment, electrical contacts, dentistry, and anti-pollution devices in cars. PtCl2(NH3)2 is used to treat some forms of cancer. Platinum-cobalt alloys have magnetic properties. It is also used in the definition of the Standard Hydrogen Electrode. Discovered by Antonio de Ulloa in South America in 1735. The name comes from the Spanish word platina which means silver. Platinum metal is generally not a health concern due to its unreactivity, however platinum compounds should be considered highly toxic.

Platinum

Name: Gold Symbol: Au Atomic Number: 79 Atomic Mass: 196.96655 amu Melting Point: 1064.43 °C (1337.5801 °K, 1947.9741 °F) Boiling Point: 2807.0 °C (3080.15 °K, 5084.6 °F)

79

AuGold

What is Gold?

Gold is gold colored. It is the most malleable and ductile metal known. There is only one stable isotope of gold, and five radioisotopes of gold, Au-195 being the most stable with a half-life of 186 days. Gold is used as a monetary standard, in jewelry, dentistry, electronics. Au-198 is used in treating cancer and some other medical conditions. Gold has been known to exist as far back as 2600 BC. Gold comes from the Anglo-Saxon word gold. Its symbol, Au, comes from the Latin word aurum, which means gold. Gold is not particularly toxic, however it is known to cause damage to the liver and kidneys in some.

Gold

Name: Mercury Symbol: Hg Atomic Number: 80 Atomic Mass: 200.59 amu Melting Point: -38.87 °C (234.28 °K, -37.966 °F) Boiling Point: 356.58 °C (629.73 °K, 673.844 °F)

80

HgMercury

What is Mercury?

Heavy silvery liquid metallic element, belongs to the zinc group. Used in thermometers, barometers and other scientific apparatus. Less reactive than zinc and cadmium, does not displace hydrogen from acids. Forms a number of complexes and organomercury compounds.

Mercury

Germicidal UV discharge tube

contains mercury.

Name: Thallium Symbol: Tl Atomic Number: 81 Atomic Mass: 204.3833 amu Melting Point: 303.5 °C (576.65 °K, 578.3 °F) Boiling Point: 1457.0 °C (1730.15 °K, 2654.6 °F)

81

TlThallium

What is Thallium?

Pure, unreacted thallium appears silvery-white and exhibits a metallic lustre. Upon reacting with air, it begins to turn bluish-grey and looks like lead. It is very malleable, and can be cut with a knife. There are two stable isotopes, and four radioisotopes, Tl-204 being the most stable with a half-life of 3.78 years. Thallium sulfate was used as a rodenticide. Thallium sulphine's conductivity changes with exposure to infrared light, this gives it a use in infrared detectors. Discovered by Sir William Crookes via spectroscopy. Its name comes from the Greek word thallos, which means green twig. Thallium and its compounds are toxic and can cause cancer.

Thallium

Name: Lead Symbol: Pb Atomic Number: 82 Atomic Mass: 207.2 amu Melting Point: 327.5 °C (600.65 °K, 621.5 °F) Boiling Point: 1740.0 °C (2013.15 °K, 3164.0 °F)

82

PbLead

What is Lead?

Heavy dull grey ductile metallic element, belongs to group 14. Used in building construction, lead-place accumulators, bullets and shot, and is part of solder, pewter, bearing metals, type metals and fusible alloys.

Lead

Dschwen, wikipedia.org Name: Bismuth Symbol: Bi Atomic Number: 83 Atomic Mass: 208.98038 amu Melting Point: 271.3 °C (544.45 °K, 520.33997 °F) Boiling Point: 1560.0 °C (1833.15 °K, 2840.0 °F)

83

BiBismuth

What is Bismuth?

White crystalline metal with a pink tinge, belongs to group 15. Most diamagnetic of all metals and has the lowest thermal conductivity of all the elements except mercury. Lead-free bismuth compounds are used in cosmetics and medical procedures. Burns in the air and produces a blue flame. In 1753, C.G. Junine first demonstrated that it was different from lead.

Bismuth

Name: Polonium Symbol: Po Atomic Number: 84 Atomic Mass: (209.0) amu Melting Point: 254.0 °C (527.15 °K, 489.2 °F) Boiling Point: 962.0 °C (1235.15 °K, 1763.6 °F)

84

PoPolonium

What is Polonium?

Rare radioactive metallic element, belongs to group 16 of the periodic table. Over 30 known isotopes exist, the most of all elements. Po-209 has a half-life of 103 years. Possible uses in heating spacecraft. Discovered by Marie Curie in 1898 in a sample of pitchblende.

Polonium

Name: Astatine Symbol: At Atomic Number: 85 Atomic Mass: (210.0) amu Melting Point: 302.0 °C (575.15 °K, 575.6 °F) Boiling Point: 337.0 °C (610.15 °K, 638.6 °F)

85

AtAstatine

What is Astatine?

Radioactive halogen element. Occurs naturally from uranium and thorium decay. At least 20 known isotopes. At-210, the most stable, has a half-life of 8.3 hours. Synthesized by nuclear bombardment in 1940 by D.R. Corson, K.R. MacKenzie and E. Segre at the University of California.

Astatine

86

RnRadon

Name: Radon Symbol: RnAtomic Number: 86 Atomic Mass: (222.0) amu Melting Point: -71.0 °C (202.15 °K, -95.8 °F) Boiling Point: -61.8 °C (211.35 °K, -79.24 °F)

Link What is Radon?

Colorless radioactive gaseous element, belongs to the noble gases. Of the twenty known isotopes, the most stable is Rn-222 with a half-life of 3.8 days. Formed by the radioactive decay of Radium-226. Radon itself decays into polonium. Used in radiotherapy. As a noble gas, it is effectively inert, though radon fluoride has been synthesized. First isolated in 1908 by Ramsey and Gray.

Radon

Name: Francium Symbol: Fr Atomic Number: 87 Atomic Mass: (223.0) amu Melting Point: 27.0 °C (300.15 °K, 80.6 °F) Boiling Point: 677.0 °C (950.15 °K, 1250.6 °F)

87

FrFrancium

What is Francium?

Radioactive element, belongs to group 1 of the periodic table. Found in uranium and thorium ores. The 22 known isotopes are all radioactive, with the most stable being Fr-223. Its existence was confirmed in 1939 by Marguerite Perey.

Francium

Name: Radium Symbol: Ra Atomic Number: 88 Atomic Mass: (226.0) amu Melting Point: 700.0 °C (973.15 °K, 1292.0 °F) Boiling Point: 1737.0 °C (2010.15 °K, 3158.6 °F)

Link

88

RaRadium

What is Radium?

Radioactive metallic element, belongs to group 2 of the periodic table. Most stable isotope, Ra-226 has a half-life of 1602 years, which decays into radon. Isolated from pitchblende in 1898 Marie and Pierre Curie.

Radium

89

AcActinium

Name: Actinium Symbol: Ac Atomic Number: 89 Atomic Mass: (227.0) amu Melting Point: 1050.0 °C (1323.15 °K, 1922.0 °F) Boiling Point: 3200.0 °C (3473.15 °K, 5792.0 °F)

What is Actinium?

Silvery radioactive metallic element, belongs to group 3 of the periodic table. The most stable isotope, Ac-227, has a half-life of 217 years. Ac-228 (half-life of 6.13 hours) also occurs in nature. There are 22 other artificial isotopes, all radioactive and having very short half-lives. Chemistry similar to lanthanum. Used as a source of alpha particles. Discovered by A. Debierne in 1899.

Actinium