Permanganate

A permanganate is the general name for a chemical compound containing the manganate(VII) ion, (MnO₄⁻). Because manganese is in the +7 oxidation state, the permanganate(VII) ion is a strong oxidizing agent. The ion has tetrahedral geometry. Permanganate solutions are purple in color and are stable in neutral or slightly alkaline media.The exact chemical reaction is dependent upon the organic contaminants present and the oxidant utilized. For example, trichloroethene (C₂HCl₃) is oxidized by sodium permanganate to form carbon dioxide (CO₂), manganese dioxide (MnO₂), sodium ions (Na⁺), hydronium ions (H⁺), and chloride ions (Cl⁻).

In an acidic solution, permanganate(VII) is reduced to the colourless +2 oxidation state of the manganese(II) (Mn²⁺) ion.

In a strongly basic solution, permanganate(VII) is reduced to the green +6 oxidation state of the manganate ion, MnO₄²⁻.

In a neutral medium however, it gets reduced to the brown +4 oxidation state of manganese dioxide MnO₂.

Production

Permanganates can be produced by oxidation of manganese compounds such as manganese chloride or manganese sulfate by strong oxidizing agents, for instance, sodium hypochlorite or lead dioxide:

Manganese(II) oxide

Manganese(II) oxide (systematically named manganese(2+) oxide(2−)) is an inorganic compound with chemical formula MnO. It forms green crystals. The compound is produced on a large scale as a component of fertilizers and food additives.

Structure, stoichiometry, reactivity

Like many monoxides, MnO adopts the rock salt structure, where cations and anions are both octahedrally coordinated. Also like many oxides, manganese(II) oxide is often nonstoichiometric: its composition can vary from MnO to MnO_1.045.

Below 118 K MnO is antiferromagnetic. MnO has the distinction of being one of the first compounds to have its magnetic structure determined by neutron diffraction, the report appearing in 1951. This study showed that the Mn²⁺ ions form a face centered cubic magnetic sub-lattice where there are ferromagnetically coupled sheets that are anti-parallel with adjacent sheets.

Manganese(II) oxide undergoes the chemical reactions typical of an ionic oxide. Upon treatment with acids, it converts to the corresponding manganese(II) salt and water. Oxidation of manganese(II) oxide gives manganese(III) oxide.

Yesterday

Yesterday or yesterdays may refer to:

Books

Music

Songs

Spirit (Leona Lewis album)

Spirit is the debut studio album by British singer-songwriter Leona Lewis, released by Syco Music in November 2007 in the United Kingdom and Ireland, followed by a worldwide release during early 2008. After winning the third series of reality singing contest The X Factor in December 2006, Lewis began recording the album in Sweden, the United Kingdom and United States, working with a variety of writers and producers. Critics praised the album for creating a contemporary album using such a variety of producers, and for showcasing Lewis's voice, though criticised her "lack of personality". The release of the album marked Lewis as the first winner of a major television talent show in both the UK and US to be given a major global launch with a debut album.

The album debuted at number one in nine countries, including the United Kingdom, United States and Germany, and peaked in the top five in a further eight countries. It held the record for the biggest digital album sales in a week ever for a new artist. The album was the sixth biggest selling of 2008 in the world, as according to the IFPI. It has gone on to sell over 8 million copies worldwide, and was the fourth best-selling album of the 2000s in the UK, where it has since sold over 3.12 million copies and remains the best-selling debut album by a female artist.

Yesterday (1985 film)

Yesterday is a 1985 Polish drama film directed by Radosław Piwowarski. The film was selected as the Polish entry for the Best Foreign Language Film at the 58th Academy Awards, but was not accepted as a nominee.

Cast

See also

References

External links