Properties

CAS Number7439-90-9
PubChem CID5416
Atomic Radius88
Atomic Volume38.9
Atomic Weight83.798
Blockp
Boiling Point-153.22
Bulk Modulus
CategoryNoble gases
Crystal StructureFace Centered Cubic
Color
Covalent Radius116
Density0.004
Electrical Resistivity
Electron Configuration[Ar] 3d10 4s2 4p6
Electrons per shell2, 8, 18, 8
Electronegativity3
Electrons36
Group18
Heat of Fusion1.64
Heat of Vaporization9.02
Ionization Potential14
Magnetic Ordering
Magnetic Susceptibility
Mass83.798
Mass Number36
Melting Point-157.36
NameKrypton
Neutrons48
Atomic Number84
Oxidation States2
Period4
PhaseGas
Poisson Ratio
Protons36
Shear Modulus
Specific Heat Capacity0.248
SymbolKr
Thermal Conductivity0
Van der Waals radius
Young's Modulus
Abundance
Abundance in Earth's crust1.5×10-8%
Abundance in Universe4×10-6%
Kr Krypton 36 83.798 18 4 p 36 -157.0 -152.0 [Ar] 3d10 4s2 4p6 2 8 18 8 0.00374 1.5E-8% Colorless Cubic: Face centered 3.0 2.966 {"1":"1350.8","2":"2350.4","3":"3565","4":"5070","5":"6240","6":"7570","7":"10710","8":"12138","9":"22274","10":"25880","11":"29700","12":"33800","13":"37700","14":"43100","15":"47500","16":"52200","17":"57100","18":"61800","19":"75800","20":"80400","21":"85300","22":"90400","23":"96300","24":"101400","25":"111100","26":"116290","27":"282500","28":"296200","29":"311400","30":"326200"} 1356 0 110 0 1.03 32.2 1.638 9.029 0.248 0.00949 0 Gas, Diamagnetic, NobleGas, Nonmetal, Stable, Natural KRIP-ton Colorless, odorless, tasteless rare noble gas. Used in lighting products. Some is used as inert filler-gas in incandescent bulbs. Some is mixed with argon in fluorescent lamps. The most important use is in flashing stroboscopic lamps that outline airport runways. Forms 1 millionth of the atmosphere. Obtained from production of liquid air. il4OOY7Zseg Krypton
By the mid-18th century, Swedish chemist Carl Wilhelm Scheele had used pyrolusite to produce chlorine.

Scheele and others were aware that pyrolusite contained a new element, but they were not able to isolate it.

Johan Gottlieb Gahn was the first to isolate an impure sample of manganese metal in 1774, by reducing the dioxide with carbon. From the Latin word magnes, magnet, from magnetic properties of pyrolusite 36 1898 Sir William Ramsay, Morris W. Travers Great Britain From the Greek word "kryptos" meaning "hidden"

Isotopes of Manganese

Standard Atomic Weight

83.798(2)

Stable Isotopes

78Kr 80Kr 82Kr 83Kr 84Kr 86Kr

Unstable Isotopes

69Kr 70Kr 71Kr 72Kr 73Kr 74Kr 75Kr 76Kr 77Kr 79Kr 81Kr 85Kr 87Kr 88Kr 89Kr 90Kr 91Kr 92Kr 93Kr 94Kr 95Kr 96Kr 97Kr 98Kr 99Kr 100Kr

Excess manganese, particularly inhalation of the powder, is toxic
Neanderthals may have used black manganese di oxide as a cosmetic 50,000 years ago
For over 2000 years, manganese dioxide has been used to make colorless glass.

Manganese dioxide is used as the cathode material in zinc-carbon and alkaline batteries.

Manganese also functions in the oxygen-evolving complex of photosynthetic plants.

The dioxide is also used in the preparation of oxygen and chlorine and in drying black paints.