Manganese easy to oxidize. Manganese metal and its common ions are paramagnetic. Manganese tarnishes slowly in air and oxidizes ("rusts") like iron in water containing dissolved oxygen. Naturally occurring manganese is composed of one stable isotope, Mn. Eighteen radioisotopes have been isolated and described, ranging in atomic weight from 46 u (Mn) to 65 u (Mn). The most stable are Mn with a half-life of 3.7 million years, Mn with a half-life of 312.3 days, and Mn with a half-life of 5.591 days. All of the remaining radioactive isotopes have half-lives of less than three hours, and the majority of less
Manganese(II) chloride Manganese(II) chloride Manganese(II) chloride describes a series of compounds with the formula MnCl(HO), where the value of x can be 0, 2, or 4. The tetrahydrate is the most common form of "manganese(II) chloride" and is the tetrahydrate with the formula MnCl·4HO. The anhydrous form and a dihydrate MnCl·2HO are also known. Like many Mn(II) species, these salts are pink, with the paleness of the color being characteristic of transition metal complexes with high spin d configurations. Manganese chloride is produced by treating manganese(IV) oxide with concentrated hydrochloric acid. This reaction was once used for the manufacture of chlorine. By