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Manganese is a chemical element; it has symbol Mn and atomic number 25. It is a hard, brittle, silvery metal, often found in minerals in combination with iron ...
Naturally occurring manganese (25 Mn) is composed of one stable isotope, 55 Mn. Twenty-seven radioisotopes have been characterized, with the most stable being 53 Mn with a half-life of 3.7 million years, 54 Mn with a half-life of 312.3 days, and 52 Mn with a half-life of 5.591 days.
Just as atomic units are given in terms of the atomic mass unit (approximately the proton mass), the physically appropriate unit of length here is the Bohr radius, which is the radius of a hydrogen atom. The Bohr radius is consequently known as the "atomic unit of length". It is often denoted by a 0 and is approximately 53 pm. Hence, the values ...
Manganese may also form mixed oxides with other metals : Bixbyite, (Fe III,Mn III) 2 O 3, a manganese(III) iron(III) oxide mineral; Jacobsite, Mn II Fe III 2 O 4, a manganese(II) iron(III) oxide mineral; Columbite, (Fe II,Mn II)Nb 2 O 6, a niobate of iron(II) and manganese(II) Tantalite, (Fe II,Mn II)Ta 2 O 6, a tantalum(V) mineral group close ...
Manganese(IV) oxide is a blackish or brown solid occurs naturally as the mineral pyrolusite, which is the main ore of manganese and a component of manganese nodules. The principal use for MnO 2 is for dry-cell batteries, such as the alkaline battery and the zinc–carbon battery. [6] Manganese(VII) oxide is dark green in its crystalline form.
Manganese is also important in photosynthetic oxygen evolution in chloroplasts in plants. The oxygen-evolving complex (OEC) is a part of photosystem II contained in the thylakoid membranes of chloroplasts; it is responsible for the terminal photooxidation of water during the light reactions of photosynthesis , and has a metalloenzyme core ...
The manganese atom transfers an oxygen atom from chlorine bleach or similar oxidant. The reaction takes its name from its inventor, Eric Jacobsen , with Tsutomu Katsuki sometimes being included. Chiral-directing catalysts are useful to organic chemists trying to control the stereochemistry of biologically active compounds and develop ...
The manganese (Mn) atom has a 3d 5 electron configuration with five unpaired electrons all of parallel spin, corresponding to a 6 S ground state. [4] The superscript 6 is the value of the multiplicity , corresponding to five unpaired electrons with parallel spin in accordance with Hund's rule.