Manganese arsenates

Sodium, potassium, sulfur 0.10 Selenium, manganese, arsenic, nickel 2. X 10- ... 

Manganese Arsenates.—Manganous Orthoarsenate, Mns(As04)a. H20, is obtained as brown needles 8 when manganese sulphate is heated with sodium orthoarsenate in a sealed tube at 175° C. 

Colloidal manganese arsenate may be obtained in an analogous way to that described for cadmium and cobalt arsenates.7 If concentrated solutions of manganous chloride and potassium dihydrogen arsenate are mixed at the ordinary temperature, a solid jelly is formed, which remains stable for weeks but finally, rose-coloured crystals separate and the jelly partly liquefies.8 The essential constituent of the jelly appears to be the monohydrogen arsenate, MnHAs04, and the crystals are the monohydrate, MnHAs04.Ha0. 

This chapter discusses the chemical mechanisms influencing the fate of trace elements (arsenic, chromium, and zinc) in a small eutrophic lake with a seasonally anoxic hypolimnion (Lake Greifen). Arsenic and chromium are redox-sensitive trace elements that may be directly involved in redox cycles, whereas zinc is indirectly influenced by the redox conditions. We will illustrate how the seasonal cycles and the variations between oxic and anoxic conditions affect the concentrations and speciation of iron, manganese, arsenic, chromium, and zinc in the water column. The redox processes occurring in the anoxic hypolimnion are discussed in detail. Interactions between major redox species and trace elements are demonstrated. 

Although iron, manganese, magnesium, calcium, and aluminum arsenates are usually too water soluble to control arsenic mobility in soils (Inskeep, McDermott and Fendorf, 2002), 187, iron, aluminum, or manganese arsenates occur in some acidic soils. In particular, scorodite may form from the partial weathering of arsenian pyrite or arsenopyrite (Inskeep, McDermott and Fendorf, 2002), 187. Calcium arsenates may be present in alkaline calcium-rich soils (Matschullat, 2000), 303 (Mandal and Suzuki, 2002), 204. 

Madison River 96 magmatic water 83 magnetic separation 397-8 Mainamoti 145 manganese arsenates 110 manganese (oxy)(hydr)oxides 93, 95, 107-8, 162, 172, 306... 

ASzMnaOs (s) 3MnO AS2O5 (s) Manganese Arsenate As2Mn30s (s) 3MnO AS2O5 (s)... 

Mn3(As04)2 MANGANESE ARSENATE 1035 Mo02CI2[g] MOLYBDENUM DICHLORIDE DIOX. (GAS) 1074... 

Sulfuryl chloride can be employed in conjunction with numerous chlorine carriers to effect substitution in either the ring or side chain. The chlorides of antimony, iron, molybdenum, and aluminum are valuable with sulfuryl chloride in effecting substitution in the ring. The chlorides of phosphorus and, to a lesser extent, manganese, arsenic, and bromine favor side-chain substitution. Sulfur accelerates both types of substitution. 

Elements that are useful for classification and discrimination include lithium, aluminum, magnesium, potassium, iron, manganese, arsenic, barium, rubidium, and strontium (Table 3). 

Manganese, arsenic, magnesium, hypochlorite, silicate + phosphate, carbaryl, carbofuran, hydrazine, NTA... 

Sphalerite or zinc blende (figure M47) is a yellow, brown, or black mineral (Zn,Ee)S. It often contains manganese, arsenic, cadmium and other elements. It is a widely distributed ore of zinc, commonly associated with galena PbS in veins and other deposits. Sphalerite is the principal ore mineral for zinc in the world. 

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