1
Hydrogen
H
Hydrogen
N
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)
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.
Electron Configuration
H = 1s1
2
Helium
He
Helium
N
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)
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.
Electron Configuration
He = 1s2
3
Lithium
Li
Lithium
N
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)
What is Lithium?
Socket silvery metal. First member of group 1 of the
periodic table. Lithium salts are used in
psychomedicine.
Electron Configuration
Li = 1s22s1
4
Beryllium
Be
Beryllium
N
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)
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.
Electron Configuration
Be = 1s22s2
5
Boron
B
Boron
N
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)
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.
Electron Configuration
B = 1s22s22p1
6
Carbon
C
Carbon
N
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)
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.
Electron Configuration
C = 1s22s22p2
7
Nitrogen
N
Nitrogen
N
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)
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.
Electron Configuration
N = 1s22s22p3
8
Oxygen
O
Oxygen
N
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)
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.
Electron Configuration
O = 1s22s22p4
9
Fluorine
F
Fluorine
N
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)
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.
Electron Configuration
F = 1s22s22p5
10
Neon
Ne
Neon
N
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)
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.
Electron Configuration
Ne = 1s22s22p6
11
Sodium
Na
Sodium
N
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)
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.
Electron Configuration
Na = 1s22s22p63s1
12
Magnesium
Mg
Magnesium
N
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)
Link
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.
Electron Configuration
Mg = 1s22s22p63s2
13
Aluminum
Al
Aluminum
N
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)
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.
Electron Configuration
Al = 1s22s22p63s23p1
14
Silicon
Si
Silicon
N
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)
Link
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.
Electron Configuration
Si = 1s22s22p63s23p2
15
Phosphorus
P
Phosphorus
N
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)
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.
Electron Configuration
P = 1s22s22p63s23p3
16
Sulfur
S
Sulfur
N
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)
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.
Electron Configuration
S = 1s22s22p63s23p4
17
Chlorine
Cl
Chlorine
N
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)
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.
Electron Configuration
Cl = 1s22s22p63s23p5
18
Argon
Ar
Argon
N
pslawinski, wikipedia.org
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)
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.
Electron Configuration
Ar = 1s22s22p63s23p6
19
Potassium
K
Potassium
N
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)
Link
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.
Electron Configuration
K = 1s22s22p63s23p6
4s1
20
Calcium
Ca
Calcium
N
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)
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.
Electron Configuration
Ca = 1s22s22p63s23p6
4s2
21
Scandium
Sc
Scandium
N
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)
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.
Electron Configuration
Sc = 1s22s22p63s23p6
4s23d1
22
Titanium
Ti
Titanium
N
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)
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.
Electron Configuration
Ti = 1s22s22p63s23p6
4s23d2
23
Vanadium
V
Vanadium
N
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)
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.
Electron Configuration
V = 1s22s22p63s23p6
4s23d3
24
Chromium
Cr
Chromium
N
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)
Link
What is Chromium?
Hard silvery transition element. Used in decorative
electroplating. Discovered in 1797 by Vauquelin.
Electron Configuration
Cr = 1s22s22p63s23p6
4s13d5
25
Manganese
Mn
Manganese
N
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)
What is Manganese?
Grey brittle metallic transition element. Rather
electropositive, combines with some non-metals when
heated. Discovered in 1774 by Scheele.
Electron Configuration
Mn = 1s22s22p63s23p6
4s23d5
26
Iron
Fe
Iron
N
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)
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.
Electron Configuration
Fe = 1s22s22p63s23p6
4s23d6
27
Cobalt
Co
Cobalt
N
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)
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.
Electron Configuration
Co = 1s22s22p63s23p6
4s23d7
28
Nickel
Ni
Nickel
N
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)
Link
What is Nickel?
Malleable ductile silvery metallic transition element.
Discovered by A.F. Cronstedt in 1751.
Electron Configuration
Ni = 1s22s22p63s23p6
4s23d8
29
Copper
Cu
Copper
N
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)
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.
Electron Configuration
Cu = 1s22s22p63s23p6
4s13d10
30
Zinc
Zn
Zinc
N
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)
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 nonmetals, reacts with dilute acids to release hydrogen.
Electron Configuration
Zn = 1s22s22p63s23p6
4s23d10
31
Gallium
Ga
Gallium
N
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)
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
Ga
other metals by diffusing into their lattice. First identified by
Francois Lecoq de Boisbaudran in 1875.
Electron Configuration
= 1s22s22p63s23p6
4s23d104p1
32
Germanium
Ge
Germanium
N
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)
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.
Electron Configuration
Ge = 1s22s22p63s23p6
4s23d104p2
33
Arsenic
As
Arsenic
N
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)
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.
Electron Configuration
As = 1s22s22p63s23p6
4s23d104p3
34
Selenium
Se
Selenium
N
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)
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.
Electron Configuration
Se = 1s22s22p63s23p6
4s23d104p4
35
Bromine
Br
Bromine
N
RTC, wikipedia.org
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)
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.
Electron Configuration
Br = 1s22s22p63s23p6
4s23d104p5
36
Krypton
Kr
Krypton
N
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)
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.
Electron Configuration
Kr = 1s22s22p63s23p6
4s23d104p6
37
Rubidium
Rb
Rubidium
N
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)
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
38
Strontium
Sr
Strontium
N
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)
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
39
Yttrium
Y
Yttrium
N
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)
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
40
Zirconium
Zr
Zirconium
N
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)
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
41
Niobium
Nb
Niobium
N
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)
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
42
Molybdenum
Mo
Molybdenum
N
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)
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,
Mo
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.
= [Kr]5s14d5
43
Technetium
Tc
Technetium
N
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)
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
Tc
properties are intermediate between rhenium and manganese.
= [Kr]5s24d5
44
Ruthenium
Ru
Ruthenium
N
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)
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
45
Rhodium
Rh
Rhodium
N
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)
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
46
Palladium
Pd
Palladium
N
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)
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
47
Silver
Ag
Silver
N
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)
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
48
Cadmium
Cd
Cadmium
N
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)
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
49
Indium
In
Indium
N
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)
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
50
Tin
Sn
Tin
N
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)
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
51
Antimony
Sb
Antimony
N
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)
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
52
Tellurium
Te
Tellurium
N
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)
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
53
Iodine
I
Iodine
N
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)
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
54
Xenon
Xe
Xenon
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)
pslawinski, wikipedia.org
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
55
Cesium
Cs
Cesium
N
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)
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
56
Barium
Ba
Barium
N
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)
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
57
Lanthanum
La
Lanthanum
N
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)
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
58
Cerium
Ce
Cerium
N
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)
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. Ce
Discovered by Martin .H. Klaproth in 1803.
= [Xe] 6s24f15d1
59
Praseodymium
Pr
Praseodymium
N
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)
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
60
Neodymium
Nd
Neodymium
N
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)
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
61
Promethium
Pm
Promethium
N
Name: Promethium
Symbol: Pm
Atomic Number: 61
Atomic Mass: (145.0) amu
Melting Point: Unknown
Boiling Point: Unknown
What is Promethium?
Soft silvery metallic element, belongs to the lanthanoids. Pm147, 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
62
Samarium
Sm
Samarium
N
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)
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
63
Europium
Eu
Europium
N
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)
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
64
Gadolinium
Gd
Gadolinium
N
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)
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
65
Terbium
Tb
Terbium
N
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)
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
66
Dysprosium
Dy
Dysprosium
N
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)
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
67
Holmium
Ho
Holmium
N
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)
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, Ho165 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.
68
Erbium
Er
Erbium
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)
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.
69
Thulium
Tm
Thulium
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)
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.
70
Ytterbium
Yb
Ytterbium
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)
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.
71
Lutetium
Lu
Lutetium
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)
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.
72
Hafnium
Hf
Hafnium
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)
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.
73
Tantalum
Ta
Tantalum
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)
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.
74
Tungsten
W
Tungsten
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)
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.
75
Rhenium
Re
Rhenium
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)
What is Rhenium?
Silvery-white metallic transition element. Obtained as a
by-product of molybdenum refinement. Rheniummolybdenum alloys are superconducting.
76
Osmium
Os
Osmium
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)
What is Osmium?
Hard blue-white metallic transition element. Found with
platinum and used in some alloys with platinum and
iridium.
77
Iridium
Ir
Iridium
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)
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.
78
Platinum
Pt
Platinum
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)
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.
79
Gold
Au
Gold
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)
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.
80
Mercury
Hg
Mercury
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)
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.
Germicidal UV discharge tube
contains mercury.
81
Thallium
Tl
Thallium
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)
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.
82
Lead
Pb
Lead
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)
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.
83
Bismuth
Bi
Bismuth
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)
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.
84
Polonium
Po
Polonium
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)
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.
85
Astatine
At
Astatine
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)
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.
86
Radon
Rn
Radon
Name: Radon
Symbol: Rn
Atomic 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.
87
Francium
Fr
Francium
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)
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.
88
Radium
Ra
Radium
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
What is Radium?
Radioactive metallic element, belongs to group 2 of the
periodic table. Most stable isotope, Ra-226 has a halflife of 1602 years, which decays into radon. Isolated
from pitchblende in 1898 Marie and Pierre Curie.
89
Actinium
Ac
Actinium
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. Ac228 (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.