Comments on: element Manganese info? http://alkaline-water.info/160/element-manganese-info/ Learn How To Separate Fact From Fiction Sat, 19 May 2012 13:51:07 +0000 hourly 1 http://wordpress.org/?v=3.3.1 By: ChemTeam http://alkaline-water.info/160/element-manganese-info/comment-page-1/#comment-204 ChemTeam Sat, 16 Jan 2010 04:16:31 +0000 http://alkaline-water.info/160/element-manganese-info/#comment-204 redox potentials: acid/base: As Mn(OH)2, it's a base. It's actually insoluble with a Ksp of 1.8 x 10^-11 redox potentials:

acid/base:

As Mn(OH)2, it’s a base. It’s actually insoluble with a Ksp of 1.8 x 10^-11

]]> By: ETAdvanceTeam http://alkaline-water.info/160/element-manganese-info/comment-page-1/#comment-203 ETAdvanceTeam Fri, 15 Jan 2010 16:09:28 +0000 http://alkaline-water.info/160/element-manganese-info/#comment-203 Mananese: Manganese is a gray-white metal resembling iron. It is a hard metal and is very brittle, fusible with difficulty, but easily oxidized. Manganese metal and its common ions are paramagnetic. This means that, while manganese metal does not form a permanent magnet, it does exhibit strong magnetic properties in the presence of an external magnetic field. The most common oxidation states of manganese are +2, +3, +4, +6 and +7, though oxidation states from +1 to +7 are observed. Mn2+ often competes with Mg2+ in biological systems, and manganese compounds where manganese is in oxidation state +7 are powerful oxidizing agents. The most stable oxidation state for manganese is +2, which has a pink to red color, and many manganese(II) compounds are known, such as manganese(II) sulfate (MnSO4) and manganese(II) chloride (MnCl2). This oxidation state is also seen in the mineral rhodochrosite, (manganese(II) carbonate). The +2 oxidation state is the state use in living organisms for essential functions; all of the other states are much more toxic. The +3 oxidation state is known, in compounds such as manganese(III) acetate, but these are quite powerful oxidizing agents. Manganese(IV) oxide (manganese dioxide, MnO2) is used as a reagent in organic chemistry for the oxidation of benzylic alcohols (i.e. adjacent to an aromatic ring). Manganese dioxide has been used since antiquity to oxidatively neutralize the greenish tinge in glass caused by trace amounts of iron contamination. MnO2 is also used in the manufacture of oxygen and chlorine, and in drying black paints. In some preparations it is a brown pigment that can be used to make paint and is a constituent of natural umber. Permanganate (+7 oxidation state) manganese compounds are purple, and can color glass an amethyst color. Potassium permanganate, sodium permanganate and barium permanganate are all potent oxidizers. Methylcyclopentadienyl manganese tricarbonyl is used as an additive in unleaded gasoline to boost octane rating and reduce engine knocking. The manganese in this unusual organometalic compound is in the +1 oxidation state. Most manangese compounds are ionic, with the exception of organometallic manganese compounds such as the one mentioned above, where manangese forms covalent pi-bonded complexes. Manganese oxides: can be acidic, basic or amphoteric, depending on the oxidation state. Manganese redox potentials (in acidic solutions): Mn(s) ===> Mn2+(aq) + 2 e- E° = 1.18 V Mn2+ (aq) ===> Mn3+(aq) + e- E° = -1.5 V Due to the large number of Mn oxidation states, you can find the table of Mn redox potentials here: Additional references: Mananese:
Manganese is a gray-white metal resembling iron. It is a hard metal and is very brittle, fusible with difficulty, but easily oxidized. Manganese metal and its common ions are paramagnetic. This means that, while manganese metal does not form a permanent magnet, it does exhibit strong magnetic properties in the presence of an external magnetic field.

The most common oxidation states of manganese are +2, +3, +4, +6 and +7, though oxidation states from +1 to +7 are observed. Mn2+ often competes with Mg2+ in biological systems, and manganese compounds where manganese is in oxidation state +7 are powerful oxidizing agents.

The most stable oxidation state for manganese is +2, which has a pink to red color, and many manganese(II) compounds are known, such as manganese(II) sulfate (MnSO4) and manganese(II) chloride (MnCl2). This oxidation state is also seen in the mineral rhodochrosite, (manganese(II) carbonate). The +2 oxidation state is the state use in living organisms for essential functions; all of the other states are much more toxic.

The +3 oxidation state is known, in compounds such as manganese(III) acetate, but these are quite powerful oxidizing agents.

Manganese(IV) oxide (manganese dioxide, MnO2) is used as a reagent in organic chemistry for the oxidation of benzylic alcohols (i.e. adjacent to an aromatic ring). Manganese dioxide has been used since antiquity to oxidatively neutralize the greenish tinge in glass caused by trace amounts of iron contamination. MnO2 is also used in the manufacture of oxygen and chlorine, and in drying black paints. In some preparations it is a brown pigment that can be used to make paint and is a constituent of natural umber.

Permanganate (+7 oxidation state) manganese compounds are purple, and can color glass an amethyst color. Potassium permanganate, sodium permanganate and barium permanganate are all potent oxidizers.

Methylcyclopentadienyl manganese tricarbonyl is used as an additive in unleaded gasoline to boost octane rating and reduce engine knocking. The manganese in this unusual organometalic compound is in the +1 oxidation state.

Most manangese compounds are ionic, with the exception of organometallic manganese compounds such as the one mentioned above, where manangese forms covalent pi-bonded complexes.

Manganese oxides: can be acidic, basic or amphoteric,
depending on the oxidation state.

Manganese redox potentials (in acidic solutions):

Mn(s) ===> Mn2+(aq) + 2 e- E° = 1.18 V
Mn2+ (aq) ===> Mn3+(aq) + e- E° = -1.5 V
Due to the large number of Mn oxidation states, you can find the table of Mn redox potentials here:

Additional references:

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