Summary
Hydrogen is a chemical element with chemical symbol H and atomic number 1. With an atomic weight of 1.00794 u, hydrogen is the lightest element on the periodic table. Its monatomic form (H) is the most abundant chemical substance in the Universe, constituting roughly 75% of all baryonic mass.
Appearance
colorless gas
Category
diatomic nonmetal
Atomic Mass
1.008
Boiling Point
20.271
Melting Point
13.99
Density
0.08988
Period
1
Phase
Gas
Summary
Helium is a chemical element with symbol He and atomic number 2. It is a colorless, odorless, tasteless, non-toxic, inert, monatomic gas that heads the noble gas group in the periodic table. Its boiling and melting points are the lowest among all the elements.
Appearance
colorless gas, exhibiting a red-orange glow when placed in a high-voltage electric field
Category
noble gas
Atomic Mass
4.0026022
Boiling Point
4.222
Melting Point
0.95
Density
0.1786
Period
1
Phase
Gas
Summary
Lithium (from Greek:λίθος lithos, "stone") is a chemical element with the symbol Li and atomic number 3. It is a soft, silver-white metal belonging to the alkali metal group of chemical elements. Under standard conditions it is the lightest metal and the least dense solid element.
Appearance
silvery-white
Category
alkali metal
Atomic Mass
6.94
Boiling Point
1603
Melting Point
453.65
Density
0.534
Period
2
Phase
Solid
Summary
Beryllium is a chemical element with symbol Be and atomic number 4. It is created through stellar nucleosynthesis and is a relatively rare element in the universe. It is a divalent element which occurs naturally only in combination with other elements in minerals.
Appearance
white-gray metallic
Category
alkaline earth metal
Atomic Mass
9.01218315
Boiling Point
2742
Melting Point
1560
Density
1.85
Period
2
Phase
Solid
Summary
Boron is a metalloid chemical element with symbol B and atomic number 5. Produced entirely by cosmic ray spallation and supernovae and not by stellar nucleosynthesis, it is a low-abundance element in both the Solar system and the Earth's crust. Boron is concentrated on Earth by the water-solubility of its more common naturally occurring compounds, the borate minerals.
Appearance
black-brown
Category
metalloid
Atomic Mass
10.81
Boiling Point
4200
Melting Point
2349
Density
2.08
Period
2
Phase
Solid
Summary
Carbon (from Latin:carbo "coal") is a chemical element with symbol C and atomic number 6. On the periodic table, it is the first (row 2) of six elements in column (group) 14, which have in common the composition of their outer electron shell. It is nonmetallic and tetravalent—making four electrons available to form covalent chemical bonds.
Appearance
Category
polyatomic nonmetal
Atomic Mass
12.011
Boiling Point
Melting Point
Density
1.821
Period
2
Phase
Solid
Summary
Nitrogen is a chemical element with symbol N and atomic number 7. It is the lightest pnictogen and at room temperature, it is a transparent, odorless diatomic gas. Nitrogen is a common element in the universe, estimated at about seventh in total abundance in the Milky Way and the Solar System.
Appearance
colorless gas, liquid or solid
Category
diatomic nonmetal
Atomic Mass
14.007
Boiling Point
77.355
Melting Point
63.15
Density
1.251
Period
2
Phase
Gas
Summary
Oxygen is a chemical element with symbol O and atomic number 8. It is a member of the chalcogen group on the periodic table and is a highly reactive nonmetal and oxidizing agent that readily forms compounds (notably oxides) with most elements. By mass, oxygen is the third-most abundant element in the universe, after hydrogen and helium.
Appearance
Category
diatomic nonmetal
Atomic Mass
15.999
Boiling Point
90.188
Melting Point
54.36
Density
1.429
Period
2
Phase
Gas
Summary
Fluorine is a chemical element with symbol F and atomic number 9. It is the lightest halogen and exists as a highly toxic pale yellow diatomic gas at standard conditions. As the most electronegative element, it is extremely reactive:almost all other elements, including some noble gases, form compounds with fluorine.
Appearance
Category
diatomic nonmetal
Atomic Mass
18.9984031636
Boiling Point
85.03
Melting Point
53.48
Density
1.696
Period
2
Phase
Gas
Summary
Neon is a chemical element with symbol Ne and atomic number 10. It is in group 18 (noble gases) of the periodic table. Neon is a colorless, odorless, inert monatomic gas under standard conditions, with about two-thirds the density of air.
Appearance
colorless gas exhibiting an orange-red glow when placed in a high voltage electric field
Category
noble gas
Atomic Mass
20.17976
Boiling Point
27.104
Melting Point
24.56
Density
0.9002
Period
2
Phase
Gas
Summary
Sodium /ˈsoʊdiəm/ is a chemical element with symbol Na (from Ancient Greek Νάτριο) and atomic number 11. It is a soft, silver-white, highly reactive metal. In the Periodic table it is in column 1 (alkali metals), and shares with the other six elements in that column that it has a single electron in its outer shell, which it readily donates, creating a positively charged atom - a cation.
Appearance
silvery white metallic
Category
alkali metal
Atomic Mass
22.989769282
Boiling Point
1156.09
Melting Point
370.944
Density
0.968
Period
3
Phase
Solid
Summary
Magnesium is a chemical element with symbol Mg and atomic number 12. It is a shiny gray solid which bears a close physical resemblance to the other five elements in the second column (Group 2, or alkaline earth metals) of the periodic table:they each have the same electron configuration in their outer electron shell producing a similar crystal structure. Magnesium is the ninth most abundant element in the universe.
Appearance
shiny grey solid
Category
alkaline earth metal
Atomic Mass
24.305
Boiling Point
1363
Melting Point
923
Density
1.738
Period
3
Phase
Solid
Summary
Aluminium (or aluminum; see different endings) is a chemical element in the boron group with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic, ductile metal. Aluminium is the third most abundant element (after oxygen and silicon), and the most abundant metal, in the Earth's crust.
Appearance
silvery gray metallic
Category
post-transition metal
Atomic Mass
26.98153857
Boiling Point
2743
Melting Point
933.47
Density
2.7
Period
3
Phase
Solid
Summary
Silicon is a chemical element with symbol Si and atomic number 14. It is a tetravalent metalloid, more reactive than germanium, the metalloid directly below it in the table. Controversy about silicon's character dates to its discovery.
Appearance
crystalline, reflective with bluish-tinged faces
Category
metalloid
Atomic Mass
28.085
Boiling Point
3538
Melting Point
1687
Density
2.329
Period
3
Phase
Solid
Summary
Phosphorus is a chemical element with symbol P and atomic number 15. As an element, phosphorus exists in two major forms—white phosphorus and red phosphorus—but due to its high reactivity, phosphorus is never found as a free element on Earth. Instead phosphorus-containing minerals are almost always present in their maximally oxidised state, as inorganic phosphate rocks.
Appearance
colourless, waxy white, yellow, scarlet, red, violet, black
Category
polyatomic nonmetal
Atomic Mass
30.9737619985
Boiling Point
Melting Point
Density
1.823
Period
3
Phase
Solid
Summary
Sulfur or sulphur (see spelling differences) is a chemical element with symbol S and atomic number 16. It is an abundant, multivalent non-metal. Under normal conditions, sulfur atoms form cyclic octatomic molecules with chemical formula S8.
Appearance
lemon yellow sintered microcrystals
Category
polyatomic nonmetal
Atomic Mass
32.06
Boiling Point
717.8
Melting Point
388.36
Density
2.07
Period
3
Phase
Solid
Summary
Chlorine is a chemical element with symbol Cl and atomic number 17. It also has a relative atomic mass of 35.5. Chlorine is in the halogen group (17) and is the second lightest halogen following fluorine.
Appearance
pale yellow-green gas
Category
diatomic nonmetal
Atomic Mass
35.45
Boiling Point
239.11
Melting Point
171.6
Density
3.2
Period
3
Phase
Gas
Summary
Argon is a chemical element with symbol Ar and atomic number 18. It is in group 18 of the periodic table and is a noble gas. Argon is the third most common gas in the Earth's atmosphere, at 0.934% (9,340 ppmv), making it over twice as abundant as the next most common atmospheric gas, water vapor (which averages about 4000 ppmv, but varies greatly), and 23 times as abundant as the next most common non-condensing atmospheric gas, carbon dioxide (400 ppmv), and more than 500 times as abundant as the next most common noble gas, neon (18 ppmv).
Appearance
colorless gas exhibiting a lilac/violet glow when placed in a high voltage electric field
Category
noble gas
Atomic Mass
39.9481
Boiling Point
87.302
Melting Point
83.81
Density
1.784
Period
3
Phase
Gas
Summary
Potassium is a chemical element with symbol K (derived from Neo-Latin, kalium) and atomic number 19. It was first isolated from potash, the ashes of plants, from which its name is derived. In the Periodic table, potassium is one of seven elements in column (group) 1 (alkali metals):they all have a single valence electron in their outer electron shell, which they readily give up to create an atom with a positive charge - a cation, and combine with anions to form salts.
Appearance
silvery gray
Category
alkali metal
Atomic Mass
39.09831
Boiling Point
1032
Melting Point
336.7
Density
0.862
Period
4
Phase
Solid
Summary
Calcium is a chemical element with symbol Ca and atomic number 20. Calcium is a soft gray alkaline earth metal, fifth-most-abundant element by mass in the Earth's crust. The ion Ca2+ is also the fifth-most-abundant dissolved ion in seawater by both molarity and mass, after sodium, chloride, magnesium, and sulfate.
Appearance
Category
alkaline earth metal
Atomic Mass
40.0784
Boiling Point
1757
Melting Point
1115
Density
1.55
Period
4
Phase
Solid
Summary
Scandium is a chemical element with symbol Sc and atomic number 21. A silvery-white metallic d-block element, it has historically been sometimes classified as a rare earth element, together with yttrium and the lanthanoids. It was discovered in 1879 by spectral analysis of the minerals euxenite and gadolinite from Scandinavia.
Appearance
silvery white
Category
transition metal
Atomic Mass
44.9559085
Boiling Point
3109
Melting Point
1814
Density
2.985
Period
4
Phase
Solid
Summary
Titanium is a chemical element with symbol Ti and atomic number 22. It is a lustrous transition metal with a silver color, low density and high strength. It is highly resistant to corrosion in sea water, aqua regia and chlorine.
Appearance
silvery grey-white metallic
Category
transition metal
Atomic Mass
47.8671
Boiling Point
3560
Melting Point
1941
Density
4.506
Period
4
Phase
Solid
Summary
Vanadium is a chemical element with symbol V and atomic number 23. It is a hard, silvery grey, ductile and malleable transition metal. The element is found only in chemically combined form in nature, but once isolated artificially, the formation of an oxide layer stabilizes the free metal somewhat against further oxidation.
Appearance
blue-silver-grey metal
Category
transition metal
Atomic Mass
50.94151
Boiling Point
3680
Melting Point
2183
Density
6
Period
4
Phase
Solid
Summary
Chromium is a chemical element with symbol Cr and atomic number 24. It is the first element in Group 6. It is a steely-gray, lustrous, hard and brittle metal which takes a high polish, resists tarnishing, and has a high melting point.
Appearance
silvery metallic
Category
transition metal
Atomic Mass
51.99616
Boiling Point
2944
Melting Point
2180
Density
7.19
Period
4
Phase
Solid
Summary
Manganese is a chemical element with symbol Mn and atomic number 25. It is not found as a free element in nature; it is often found in combination with iron, and in many minerals. Manganese is a metal with important industrial metal alloy uses, particularly in stainless steels.
Appearance
silvery metallic
Category
transition metal
Atomic Mass
54.9380443
Boiling Point
2334
Melting Point
1519
Density
7.21
Period
4
Phase
Solid
Summary
Iron is a chemical element with symbol Fe (from Latin:ferrum) and atomic number 26. It is a metal in the first transition series. It is by mass the most common element on Earth, forming much of Earth's outer and inner core.
Appearance
lustrous metallic with a grayish tinge
Category
transition metal
Atomic Mass
55.8452
Boiling Point
3134
Melting Point
1811
Density
7.874
Period
4
Phase
Solid
Summary
Cobalt is a chemical element with symbol Co and atomic number 27. Like nickel, cobalt in the Earth's crust is found only in chemically combined form, save for small deposits found in alloys of natural meteoric iron. The free element, produced by reductive smelting, is a hard, lustrous, silver-gray metal.
Appearance
hard lustrous gray metal
Category
transition metal
Atomic Mass
58.9331944
Boiling Point
3200
Melting Point
1768
Density
8.9
Period
4
Phase
Solid
Summary
Nickel is a chemical element with symbol Ni and atomic number 28. It is a silvery-white lustrous metal with a slight golden tinge. Nickel belongs to the transition metals and is hard and ductile.
Appearance
lustrous, metallic, and silver with a gold tinge
Category
transition metal
Atomic Mass
58.69344
Boiling Point
3003
Melting Point
1728
Density
8.908
Period
4
Phase
Solid
Summary
Copper is a chemical element with symbol Cu (from Latin:cuprum) and atomic number 29. It is a soft, malleable and ductile metal with very high thermal and electrical conductivity. A freshly exposed surface of pure copper has a reddish-orange color.
Appearance
red-orange metallic luster
Category
transition metal
Atomic Mass
63.5463
Boiling Point
2835
Melting Point
1357.77
Density
8.96
Period
4
Phase
Solid
Summary
Zinc, in commerce also spelter, is a chemical element with symbol Zn and atomic number 30. It is the first element of group 12 of the periodic table. In some respects zinc is chemically similar to magnesium:its ion is of similar size and its only common oxidation state is +2.
Appearance
silver-gray
Category
transition metal
Atomic Mass
65.382
Boiling Point
1180
Melting Point
692.68
Density
7.14
Period
4
Phase
Solid
Summary
Gallium is a chemical element with symbol Ga and atomic number 31. Elemental gallium does not occur in free form in nature, but as the gallium(III) compounds that are in trace amounts in zinc ores and in bauxite. Gallium is a soft, silvery metal, and elemental gallium is a brittle solid at low temperatures, and melts at 29.76 °C (85.57 °F) (slightly above room temperature).
Appearance
silver-white
Category
post-transition metal
Atomic Mass
69.7231
Boiling Point
2673
Melting Point
302.9146
Density
5.91
Period
4
Phase
Solid
Summary
Germanium is a chemical element with symbol Ge and atomic number 32. It is a lustrous, hard, grayish-white metalloid in the carbon group, chemically similar to its group neighbors tin and silicon. Purified germanium is a semiconductor, with an appearance most similar to elemental silicon.
Appearance
grayish-white
Category
metalloid
Atomic Mass
72.6308
Boiling Point
3106
Melting Point
1211.4
Density
5.323
Period
4
Phase
Solid
Summary
Arsenic is a chemical element with symbol As and atomic number 33. Arsenic occurs in many minerals, usually in conjunction with sulfur and metals, and also as a pure elemental crystal. Arsenic is a metalloid.
Appearance
metallic grey
Category
metalloid
Atomic Mass
74.9215956
Boiling Point
Melting Point
Density
5.727
Period
4
Phase
Solid
Summary
Selenium is a chemical element with symbol Se and atomic number 34. It is a nonmetal with properties that are intermediate between those of its periodic table column-adjacent chalcogen elements sulfur and tellurium. It rarely occurs in its elemental state in nature, or as pure ore compounds.
Appearance
black, red, and gray (not pictured) allotropes
Category
polyatomic nonmetal
Atomic Mass
78.9718
Boiling Point
958
Melting Point
494
Density
4.81
Period
4
Phase
Solid
Summary
Bromine (from Ancient Greek:βρῶμος, brómos, meaning "stench") is a chemical element with symbol Br, and atomic number 35. It is a halogen. The element was isolated independently by two chemists, Carl Jacob Löwig and Antoine Jerome Balard, in 1825–1826.
Appearance
Category
diatomic nonmetal
Atomic Mass
79.904
Boiling Point
332
Melting Point
265.8
Density
3.1028
Period
4
Phase
Liquid
Summary
Krypton (from Greek:κρυπτός kryptos "the hidden one") is a chemical element with symbol Kr and atomic number 36. It is a member of group 18 (noble gases) elements. A colorless, odorless, tasteless noble gas, krypton occurs in trace amounts in the atmosphere, is isolated by fractionally distilling liquefied air, and is often used with other rare gases in fluorescent lamps.
Appearance
colorless gas, exhibiting a whitish glow in a high electric field
Category
noble gas
Atomic Mass
83.7982
Boiling Point
119.93
Melting Point
115.78
Density
3.749
Period
4
Phase
Gas
Summary
Rubidium is a chemical element with symbol Rb and atomic number 37. Rubidium is a soft, silvery-white metallic element of the alkali metal group, with an atomic mass of 85.4678. Elemental rubidium is highly reactive, with properties similar to those of other alkali metals, such as very rapid oxidation in air.
Appearance
grey white
Category
alkali metal
Atomic Mass
85.46783
Boiling Point
961
Melting Point
312.45
Density
1.532
Period
5
Phase
Solid
Summary
Strontium is a chemical element with symbol Sr and atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when it is exposed to air.
Appearance
Category
alkaline earth metal
Atomic Mass
87.621
Boiling Point
1650
Melting Point
1050
Density
2.64
Period
5
Phase
Solid
Summary
Yttrium is a chemical element with symbol Y and atomic number 39. It is a silvery-metallic transition metal chemically similar to the lanthanides and it has often been classified as a "rare earth element". Yttrium is almost always found combined with the lanthanides in rare earth minerals and is never found in nature as a free element.
Appearance
silvery white
Category
transition metal
Atomic Mass
88.905842
Boiling Point
3203
Melting Point
1799
Density
4.472
Period
5
Phase
Solid
Summary
Zirconium is a chemical element with symbol Zr and atomic number 40. The name of zirconium is taken from the name of the mineral zircon, the most important source of zirconium. The word zircon comes from the Persian word zargun زرگون, meaning "gold-colored".
Appearance
silvery white
Category
transition metal
Atomic Mass
91.2242
Boiling Point
4650
Melting Point
2128
Density
6.52
Period
5
Phase
Solid
Summary
Niobium, formerly columbium, is a chemical element with symbol Nb (formerly Cb) and atomic number 41. It is a soft, grey, ductile transition metal, which is often found in the pyrochlore mineral, the main commercial source for niobium, and columbite. The name comes from Greek mythology:Niobe, daughter of Tantalus since it is so similar to tantalum.
Appearance
gray metallic, bluish when oxidized
Category
transition metal
Atomic Mass
92.906372
Boiling Point
5017
Melting Point
2750
Density
8.57
Period
5
Phase
Solid
Summary
Molybdenum is a chemical element with symbol Mo and atomic number 42. The name is from Neo-Latin molybdaenum, from Ancient Greek Μόλυβδος molybdos, meaning lead, since its ores were confused with lead ores. Molybdenum minerals have been known throughout history, but the element was discovered (in the sense of differentiating it as a new entity from the mineral salts of other metals) in 1778 by Carl Wilhelm Scheele.
Appearance
gray metallic
Category
transition metal
Atomic Mass
95.951
Boiling Point
4912
Melting Point
2896
Density
10.28
Period
5
Phase
Solid
Summary
Technetium (/tɛkˈniːʃiəm/) is a chemical element with symbol Tc and atomic number 43. It is the element with the lowest atomic number in the periodic table that has no stable isotopes:every form of it is radioactive. Nearly all technetium is produced synthetically, and only minute amounts are found in nature.
Appearance
shiny gray metal
Category
transition metal
Atomic Mass
98
Boiling Point
4538
Melting Point
2430
Density
11
Period
5
Phase
Solid
Summary
Ruthenium is a chemical element with symbol Ru and atomic number 44. It is a rare transition metal belonging to the platinum group of the periodic table. Like the other metals of the platinum group, ruthenium is inert to most other chemicals.
Appearance
silvery white metallic
Category
transition metal
Atomic Mass
101.072
Boiling Point
4423
Melting Point
2607
Density
12.45
Period
5
Phase
Solid
Summary
Rhodium is a chemical element with symbol Rh and atomic number 45. It is a rare, silvery-white, hard, and chemically inert transition metal. It is a member of the platinum group.
Appearance
silvery white metallic
Category
transition metal
Atomic Mass
102.905502
Boiling Point
3968
Melting Point
2237
Density
12.41
Period
5
Phase
Solid
Summary
Palladium is a chemical element with symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by William Hyde Wollaston. He named it after the asteroid Pallas, which was itself named after the epithet of the Greek goddess Athena, acquired by her when she slew Pallas.
Appearance
silvery white
Category
transition metal
Atomic Mass
106.421
Boiling Point
3236
Melting Point
1828.05
Density
12.023
Period
5
Phase
Solid
Summary
Silver is a chemical element with symbol Ag (Greek:άργυρος árguros, Latin:argentum, both from the Indo-European root *h₂erǵ- for "grey" or "shining") and atomic number 47. A soft, white, lustrous transition metal, it possesses the highest electrical conductivity, thermal conductivity and reflectivity of any metal. The metal occurs naturally in its pure, free form (native silver), as an alloy with gold and other metals, and in minerals such as argentite and chlorargyrite.
Appearance
lustrous white metal
Category
transition metal
Atomic Mass
107.86822
Boiling Point
2435
Melting Point
1234.93
Density
10.49
Period
5
Phase
Solid
Summary
Cadmium is a chemical element with symbol Cd and atomic number 48. This soft, bluish-white metal is chemically similar to the two other stable metals in group 12, zinc and mercury. Like zinc, it prefers oxidation state +2 in most of its compounds and like mercury it shows a low melting point compared to transition metals.
Appearance
silvery bluish-gray metallic
Category
transition metal
Atomic Mass
112.4144
Boiling Point
1040
Melting Point
594.22
Density
8.65
Period
5
Phase
Solid
Summary
Indium is a chemical element with symbol In and atomic number 49. It is a post-transition metallic element that is rare in Earth's crust. The metal is very soft, malleable and easily fusible, with a melting point higher than sodium, but lower than lithium or tin.
Appearance
silvery lustrous gray
Category
post-transition metal
Atomic Mass
114.8181
Boiling Point
2345
Melting Point
429.7485
Density
7.31
Period
5
Phase
Solid
Summary
Tin is a chemical element with the symbol Sn (for Latin:stannum) and atomic number 50. It is a main group metal in group 14 of the periodic table. Tin shows a chemical similarity to both neighboring group-14 elements, germanium and lead, and has two possible oxidation states, +2 and the slightly more stable +4.
Appearance
silvery-white (beta, β) or gray (alpha, α)
Category
post-transition metal
Atomic Mass
118.7107
Boiling Point
2875
Melting Point
505.08
Density
7.365
Period
5
Phase
Solid
Summary
Antimony is a chemical element with symbol Sb (from Latin:stibium) and atomic number 51. A lustrous gray metalloid, it is found in nature mainly as the sulfide mineral stibnite (Sb2S3). Antimony compounds have been known since ancient times and were used for cosmetics; metallic antimony was also known, but it was erroneously identified as lead upon its discovery.
Appearance
silvery lustrous gray
Category
metalloid
Atomic Mass
121.7601
Boiling Point
1908
Melting Point
903.78
Density
6.697
Period
5
Phase
Solid
Summary
Tellurium is a chemical element with symbol Te and atomic number 52. It is a brittle, mildly toxic, rare, silver-white metalloid. Tellurium is chemically related to selenium and sulfur.
Appearance
Category
metalloid
Atomic Mass
127.603
Boiling Point
1261
Melting Point
722.66
Density
6.24
Period
5
Phase
Solid
Summary
Iodine is a chemical element with symbol I and atomic number 53. The name is from Greek ἰοειδής ioeidēs, meaning violet or purple, due to the color of iodine vapor. Iodine and its compounds are primarily used in nutrition, and industrially in the production of acetic acid and certain polymers.
Appearance
lustrous metallic gray, violet as a gas
Category
diatomic nonmetal
Atomic Mass
126.904473
Boiling Point
457.4
Melting Point
386.85
Density
4.933
Period
5
Phase
Solid
Summary
Xenon is a chemical element with symbol Xe and atomic number 54. It is a colorless, dense, odorless noble gas, that occurs in the Earth's atmosphere in trace amounts. Although generally unreactive, xenon can undergo a few chemical reactions such as the formation of xenon hexafluoroplatinate, the first noble gas compound to be synthesized.
Appearance
colorless gas, exhibiting a blue glow when placed in a high voltage electric field
Category
noble gas
Atomic Mass
131.2936
Boiling Point
165.051
Melting Point
161.4
Density
5.894
Period
5
Phase
Gas
Summary
Caesium or cesium is a chemical element with symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal with a melting point of 28 °C (82 °F), which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium is an alkali metal and has physical and chemical properties similar to those of rubidium and potassium.
Appearance
silvery gold
Category
alkali metal
Atomic Mass
132.905451966
Boiling Point
944
Melting Point
301.7
Density
1.93
Period
6
Phase
Solid
Summary
Barium is a chemical element with symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Because of its high chemical reactivity barium is never found in nature as a free element.
Appearance
Category
alkaline earth metal
Atomic Mass
137.3277
Boiling Point
2118
Melting Point
1000
Density
3.51
Period
6
Phase
Solid
Summary
Lanthanum is a soft, ductile, silvery-white metallic chemical element with symbol La and atomic number 57. It tarnishes rapidly when exposed to air and is soft enough to be cut with a knife. It gave its name to the lanthanide series, a group of 15 similar elements between lanthanum and lutetium in the periodic table:it is also sometimes considered the first element of the 6th-period transition metals.
Appearance
silvery white
Category
lanthanide
Atomic Mass
138.905477
Boiling Point
3737
Melting Point
1193
Density
6.162
Period
6
Phase
Solid
Summary
Hafnium is a chemical element with symbol Hf and atomic number 72. A lustrous, silvery gray, tetravalent transition metal, hafnium chemically resembles zirconium and is found in zirconium minerals. Its existence was predicted by Dmitri Mendeleev in 1869, though it was not identified until 1923, making it the penultimate stable element to be discovered (rhenium was identified two years later).
Appearance
steel gray
Category
transition metal
Atomic Mass
178.492
Boiling Point
4876
Melting Point
2506
Density
13.31
Period
6
Phase
Solid
Summary
Tantalum is a chemical element with symbol Ta and atomic number 73. Previously known as tantalium, its name comes from Tantalus, an antihero from Greek mythology. Tantalum is a rare, hard, blue-gray, lustrous transition metal that is highly corrosion-resistant.
Appearance
gray blue
Category
transition metal
Atomic Mass
180.947882
Boiling Point
5731
Melting Point
3290
Density
16.69
Period
6
Phase
Solid
Summary
Tungsten, also known as wolfram, is a chemical element with symbol W and atomic number 74. The word tungsten comes from the Swedish language tung sten, which directly translates to heavy stone. Its name in Swedish is volfram, however, in order to distinguish it from scheelite, which in Swedish is alternatively named tungsten.
Appearance
grayish white, lustrous
Category
transition metal
Atomic Mass
183.841
Boiling Point
6203
Melting Point
3695
Density
19.25
Period
6
Phase
Solid
Summary
Rhenium is a chemical element with symbol Re and atomic number 75. It is a silvery-white, heavy, third-row transition metal in group 7 of the periodic table. With an estimated average concentration of 1 part per billion (ppb), rhenium is one of the rarest elements in the Earth's crust.
Appearance
silvery-grayish
Category
transition metal
Atomic Mass
186.2071
Boiling Point
5869
Melting Point
3459
Density
21.02
Period
6
Phase
Solid
Summary
Osmium (from Greek osme (ὀσμή) meaning "smell") is a chemical element with symbol Os and atomic number 76. It is a hard, brittle, bluish-white transition metal in the platinum group that is found as a trace element in alloys, mostly in platinum ores. Osmium is the densest naturally occurring element, with a density of 22.59 g/cm3.
Appearance
silvery, blue cast
Category
transition metal
Atomic Mass
190.233
Boiling Point
5285
Melting Point
3306
Density
22.59
Period
6
Phase
Solid
Summary
Iridium is a chemical element with symbol Ir and atomic number 77. A very hard, brittle, silvery-white transition metal of the platinum group, iridium is generally credited with being the second densest element (after osmium) based on measured density, although calculations involving the space lattices of the elements show that iridium is denser. It is also the most corrosion-resistant metal, even at temperatures as high as 2000 °C. Although only certain molten salts and halogens are corrosive to solid iridium, finely divided iridium dust is much more reactive and can be flammable.
Appearance
silvery white
Category
transition metal
Atomic Mass
192.2173
Boiling Point
4403
Melting Point
2719
Density
22.56
Period
6
Phase
Solid
Summary
Platinum is a chemical element with symbol Pt and atomic number 78. It is a dense, malleable, ductile, highly unreactive, precious, gray-white transition metal. Its name is derived from the Spanish term platina, which is literally translated into "little silver".
Appearance
silvery white
Category
transition metal
Atomic Mass
195.0849
Boiling Point
4098
Melting Point
2041.4
Density
21.45
Period
6
Phase
Solid
Summary
Gold is a chemical element with symbol Au (from Latin:aurum) and atomic number 79. In its purest form, it is a bright, slightly reddish yellow, dense, soft, malleable and ductile metal. Chemically, gold is a transition metal and a group 11 element.
Appearance
metallic yellow
Category
transition metal
Atomic Mass
196.9665695
Boiling Point
3243
Melting Point
1337.33
Density
19.3
Period
6
Phase
Solid
Summary
Mercury is a chemical element with symbol Hg and atomic number 80. It is commonly known as quicksilver and was formerly named hydrargyrum (/haɪˈdrɑːrdʒərəm/). A heavy, silvery d-block element, mercury is the only metallic element that is liquid at standard conditions for temperature and pressure; the only other element that is liquid under these conditions is bromine, though metals such as caesium, gallium, and rubidium melt just above room temperature.
Appearance
silvery
Category
transition metal
Atomic Mass
200.5923
Boiling Point
629.88
Melting Point
234.321
Density
13.534
Period
6
Phase
Liquid
Summary
Thallium is a chemical element with symbol Tl and atomic number 81. This soft gray post-transition metal is not found free in nature. When isolated, it resembles tin, but discolors when exposed to air.
Appearance
silvery white
Category
post-transition metal
Atomic Mass
204.38
Boiling Point
1746
Melting Point
577
Density
11.85
Period
6
Phase
Solid
Summary
Lead (/lɛd/) is a chemical element in the carbon group with symbol Pb (from Latin:plumbum) and atomic number 82. Lead is a soft, malleable and heavy post-transition metal. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed to air.
Appearance
metallic gray
Category
post-transition metal
Atomic Mass
207.21
Boiling Point
2022
Melting Point
600.61
Density
11.34
Period
6
Phase
Solid
Summary
Bismuth is a chemical element with symbol Bi and atomic number 83. Bismuth, a pentavalent post-transition metal, chemically resembles arsenic and antimony. Elemental bismuth may occur naturally, although its sulfide and oxide form important commercial ores.
Appearance
lustrous silver
Category
post-transition metal
Atomic Mass
208.980401
Boiling Point
1837
Melting Point
544.7
Density
9.78
Period
6
Phase
Solid
Summary
Polonium is a chemical element with symbol Po and atomic number 84, discovered in 1898 by Marie Curie and Pierre Curie. A rare and highly radioactive element with no stable isotopes, polonium is chemically similar to bismuth and tellurium, and it occurs in uranium ores. Applications of polonium are few.
Appearance
silvery
Category
post-transition metal
Atomic Mass
209
Boiling Point
1235
Melting Point
527
Density
9.196
Period
6
Phase
Solid
Summary
Astatine is a very rare radioactive chemical element with the chemical symbol At and atomic number 85. It occurs on Earth as the decay product of various heavier elements. All its isotopes are short-lived; the most stable is astatine-210, with a half-life of 8.1 hours.
Appearance
unknown, probably metallic
Category
metalloid
Atomic Mass
210
Boiling Point
610
Melting Point
575
Density
6.35
Period
6
Phase
Solid
Summary
Radon is a chemical element with symbol Rn and atomic number 86. It is a radioactive, colorless, odorless, tasteless noble gas, occurring naturally as a decay product of radium. Its most stable isotope, 222Rn, has a half-life of 3.8 days.
Appearance
colorless gas, occasionally glows green or red in discharge tubes
Category
noble gas
Atomic Mass
222
Boiling Point
211.5
Melting Point
202
Density
9.73
Period
6
Phase
Gas
Summary
Francium is a chemical element with symbol Fr and atomic number 87. It used to be known as eka-caesium and actinium K. It is the second-least electronegative element, behind only caesium. Francium is a highly radioactive metal that decays into astatine, radium, and radon.
Appearance
Category
alkali metal
Atomic Mass
223
Boiling Point
950
Melting Point
300
Density
1.87
Period
7
Phase
Solid
Summary
Radium is a chemical element with symbol Ra and atomic number 88. It is the sixth element in group 2 of the periodic table, also known as the alkaline earth metals. Pure radium is almost colorless, but it readily combines with nitrogen (rather than oxygen) on exposure to air, forming a black surface layer of radium nitride (Ra3N2).
Appearance
silvery white metallic
Category
alkaline earth metal
Atomic Mass
226
Boiling Point
2010
Melting Point
1233
Density
5.5
Period
7
Phase
Solid
Summary
Actinium is a radioactive chemical element with symbol Ac (not to be confused with the abbreviation for an acetyl group) and atomic number 89, which was discovered in 1899. It was the first non-primordial radioactive element to be isolated. Polonium, radium and radon were observed before actinium, but they were not isolated until 1902.
Appearance
Category
actinide
Atomic Mass
227
Boiling Point
3500
Melting Point
1500
Density
10
Period
7
Phase
Solid
Summary
Rutherfordium is a chemical element with symbol Rf and atomic number 104, named in honor of physicist Ernest Rutherford. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, 267Rf, has a half-life of approximately 1.3 hours. In the periodic table of the elements, it is a d - block element and the second of the fourth - row transition elements.
Appearance
Category
transition metal
Atomic Mass
267
Boiling Point
5800
Melting Point
2400
Density
23.2
Period
7
Phase
Solid
Summary
Dubnium is a chemical element with symbol Db and atomic number 105. It is named after the town of Dubna in Russia (north of Moscow), where it was first produced. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, dubnium-268, has a half-life of approximately 28 hours.
Appearance
Category
transition metal
Atomic Mass
268
Boiling Point
Melting Point
Density
29.3
Period
7
Phase
Solid
Summary
Seaborgium is a synthetic element with symbol Sg and atomic number 106. Its most stable isotope 271Sg has a half-life of 1.9 minutes. A more recently discovered isotope 269Sg has a potentially slightly longer half-life (ca.
Appearance
Category
transition metal
Atomic Mass
269
Boiling Point
Melting Point
Density
35
Period
7
Phase
Solid
Summary
Bohrium is a chemical element with symbol Bh and atomic number 107. It is named after Danish physicist Niels Bohr. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, 270Bh, has a half-life of approximately 61 seconds.
Appearance
Category
transition metal
Atomic Mass
270
Boiling Point
Melting Point
Density
37.1
Period
7
Phase
Solid
Summary
Hassium is a chemical element with symbol Hs and atomic number 108, named after the German state of Hesse. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and radioactive; the most stable known isotope, 269Hs, has a half-life of approximately 9.7 seconds, although an unconfirmed metastable state, 277mHs, may have a longer half-life of about 130 seconds. More than 100 atoms of hassium have been synthesized to date.
Appearance
Category
transition metal
Atomic Mass
269
Boiling Point
Melting Point
126
Density
40.7
Period
7
Phase
Solid
Summary
Meitnerium is a chemical element with symbol Mt and atomic number 109. It is an extremely radioactive synthetic element (an element not found in nature that can be created in a laboratory). The most stable known isotope, meitnerium-278, has a half-life of 7.6 seconds.
Appearance
Category
unknown, probably transition metal
Atomic Mass
278
Boiling Point
Melting Point
Density
37.4
Period
7
Phase
Solid
Summary
Darmstadtium is a chemical element with symbol Ds and atomic number 110. It is an extremely radioactive synthetic element. The most stable known isotope, darmstadtium-281, has a half-life of approximately 10 seconds.
Appearance
Category
unknown, probably transition metal
Atomic Mass
281
Boiling Point
Melting Point
Density
34.8
Period
7
Phase
Solid
Summary
Roentgenium is a chemical element with symbol Rg and atomic number 111. It is an extremely radioactive synthetic element (an element that can be created in a laboratory but is not found in nature); the most stable known isotope, roentgenium-282, has a half-life of 2.1 minutes. Roentgenium was first created in 1994 by the GSI Helmholtz Centre for Heavy Ion Research near Darmstadt, Germany.
Appearance
Category
unknown, probably transition metal
Atomic Mass
282
Boiling Point
Melting Point
Density
28.7
Period
7
Phase
Solid
Summary
Copernicium is a chemical element with symbol Cn and atomic number 112. It is an extremely radioactive synthetic element that can only be created in a laboratory. The most stable known isotope, copernicium-285, has a half-life of approximately 29 seconds, but it is possible that this copernicium isotope may have a nuclear isomer with a longer half-life, 8.9 min.
Appearance
Category
transition metal
Atomic Mass
285
Boiling Point
3570
Melting Point
Density
23.7
Period
7
Phase
Gas
Summary
Nihonium is a chemical element with atomic number 113. It has a symbol Nh. It is a synthetic element (an element that can be created in a laboratory but is not found in nature) and is extremely radioactive; its most stable known isotope, nihonium-286, has a half-life of 20 seconds.
Appearance
Category
unknown, probably transition metal
Atomic Mass
286
Boiling Point
1430
Melting Point
700
Density
16
Period
7
Phase
Solid
Summary
Flerovium is a superheavy artificial chemical element with symbol Fl and atomic number 114. It is an extremely radioactive synthetic element. The element is named after the Flerov Laboratory of Nuclear Reactions of the Joint Institute for Nuclear Research in Dubna, Russia, where the element was discovered in 1998.
Appearance
Category
post-transition metal
Atomic Mass
289
Boiling Point
420
Melting Point
340
Density
14
Period
7
Phase
Solid
Summary
Moscovium is the name of a synthetic superheavy element in the periodic table that has the symbol Mc and has the atomic number 115. It is an extremely radioactive element; its most stable known isotope, moscovium-289, has a half-life of only 220 milliseconds. It is also known as eka-bismuth or simply element 115.
Appearance
Category
unknown, probably post-transition metal
Atomic Mass
289
Boiling Point
1400
Melting Point
670
Density
13.5
Period
7
Phase
Solid
Summary
Livermorium is a synthetic superheavy element with symbol Lv and atomic number 116. It is an extremely radioactive element that has only been created in the laboratory and has not been observed in nature. The element is named after the Lawrence Livermore National Laboratory in the United States, which collaborated with the Joint Institute for Nuclear Research in Dubna, Russia to discover livermorium in 2000.
Appearance
Category
unknown, probably post-transition metal
Atomic Mass
293
Boiling Point
1085
Melting Point
709
Density
12.9
Period
7
Phase
Solid
Summary
Tennessine is a superheavy artificial chemical element with an atomic number of 117 and a symbol of Ts. Also known as eka-astatine or element 117, it is the second-heaviest known element and penultimate element of the 7th period of the periodic table. As of 2016, fifteen tennessine atoms have been observed:six when it was first synthesized in 2010, seven in 2012, and two in 2014.
Appearance
Category
unknown, probably metalloid
Atomic Mass
294
Boiling Point
883
Melting Point
723
Density
7.17
Period
7
Phase
Solid
Summary
Oganesson is IUPAC's name for the transactinide element with the atomic number 118 and element symbol Og. It is also known as eka-radon or element 118, and on the periodic table of the elements it is a p-block element and the last one of the 7th period. Oganesson is currently the only synthetic member of group 18.
Appearance
Category
unknown, predicted to be noble gas
Atomic Mass
294
Boiling Point
350
Melting Point
Density
4.95
Period
7
Phase
Solid