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APHA
SMWW 3500-Mn
Manganese
2023
3
Standard methods for the examination of water and wastewater (543.3 APHA 24th ed. Ref. Treatises&monographs FL2)
Manganese (Mn) is the first element in Group VIIB in the periodic table. It has an atomic number of 25, an atomic weight of 54.94, and common valences of 2, 4, and 7 (and more rarely, valences of 1, 3, 5, and 6). The average abundance of Mn in the earth’s crust is 1060 ppm; in soils it is 61 to 1010 ppm; in streams it is 7 μg/L, and in groundwaters it is <0.1 mg/L. Manganese is associated with iron minerals, and occurs in nodules in ocean, fresh waters, and soils. The common ores are pyrolusite (MnO2) and psilomelane. Manganese is used in steel alloys, batteries, and food additives...