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Manganese(II) nitrate is the precursor to manganese(II) carbonate (MnCO 3), which is used in fertilizers and as a colourant. The advantage of this method, based on the use of ammonia (NH 3) and carbon dioxide (CO 2) as reaction intermediates, being that the side product ammonium nitrate (NH 4 NO 3) is also useful as a fertilizer. [1]
For example, addition of potassium permanganate to an aqueous solution of sugar and sodium hydroxide produces the chemical chameleon reaction, which involves dramatic color changes associated with the various oxidation states of manganese. A related vigorous reaction is exploited as a fire starter in survival kits.
One method starts with natural manganese dioxide and converts it using dinitrogen tetroxide and water to a manganese(II) nitrate solution. Evaporation of the water leaves the crystalline nitrate salt. At temperatures of 400 °C, the salt decomposes, releasing N 2 O 4 and leaving a residue of purified manganese dioxide. [8]
The most reactive metals, such as sodium, will react with cold water to produce hydrogen and the metal hydroxide: 2 Na (s) + 2 H 2 O (l) →2 NaOH (aq) + H 2 (g) Metals in the middle of the reactivity series, such as iron , will react with acids such as sulfuric acid (but not water at normal temperatures) to give hydrogen and a metal salt ...
The following chart shows the solubility of various ionic compounds in water at 1 atm pressure and room temperature (approx. 25 °C, 298.15 K). "Soluble" means the ionic compound doesn't precipitate, while "slightly soluble" and "insoluble" mean that a solid will precipitate; "slightly soluble" compounds like calcium sulfate may require heat to precipitate.
The tables below provides information on the variation of solubility of different substances (mostly inorganic compounds) in water with temperature, at one atmosphere pressure. Units of solubility are given in grams of substance per 100 millilitres of water (g/100 ml), unless shown otherwise. The substances are listed in alphabetical order.
Potassium permanganate will decompose into potassium manganate, manganese dioxide and oxygen gas: 2 KMnO 4 → K 2 MnO 4 + MnO 2 + O 2. This reaction is a laboratory method to prepare oxygen, but produces samples of potassium manganate contaminated with MnO 2. The former is soluble and the latter is not.
Manganese(II) oxide is an inorganic compound with chemical formula MnO. [2] It forms green crystals. The compound is produced on a large scale as a component of fertilizers and food additives .