Mohr's Salt, ammonium iron sulfate, is a double salt of iron sulfate and ammonium sulfate, with the formula This article does not cite its references or sources. ... Molar mass is the mass of one mole of a chemical element or chemical compound. ... In chemistry, the standard state of a material is its state at 1 bar (100 kilopascals) and 25 degrees Celsius (298. ... A ball-and-stick model of the ammonium cation Fumes from hydrochloric acid and ammonia forming a white cloud of ammonium chloride Ammonium is also an old name for the Siwa Oasis in western Egypt. ... General Name, Symbol, Number iron, Fe, 26 Chemical series transition metals Group, Period, Block 8, 4, d Appearance lustrous metallic with a grayish tinge Standard atomic weight 55. ... In inorganic chemistry, a sulfate (IUPAC-recommended spelling; also sulphate in British English) is a salt of sulfuric acid. ... A magnified crystal of a salt (halite/sodium chloride) Salt covering the floor of Bad Water in Death Valley, CA, the lowest point in the US. A salt, in chemistry, is defined as the product formed from the neutralisation reaction of acids and bases. ... Iron(II) sulfate, also known as ferrous sulfate and as copperas (FeSO4) is an example of an ionic compound. ... Ammonium sulphate, [NH4]2[SO4] contains 21% nitrogen as ammonia and 24% sulfur as sulfate. ...

[NH₄]₂[Fe][SO₄]₂·6H₂O or Fe[SO₄].[NH₄]₂[SO₄].6H₂O

Mohr's salt is preferred over iron(II) sulfate for titration purposes as it is much less affected by oxygen in the air than iron(II) sulphate, solutions of which tend to oxidise to iron(III). The oxidation of solutions of iron(II) is very pH dependent, occurring much more readily at high pH. The ammonium ions make solutions of Mohr's salt slightly acidic, which prevents this oxidation occurring. The relevant equation for this is: Titration setup: the titrant drops from the burette into the analyte solution in the flask. ... General Name, Symbol, Number oxygen, O, 8 Chemical series nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Standard atomic weight 15. ...

so the presence of protons keeps this equilibrium to the left, the Fe(II) side.

Mohr's salt is named after the German chemist Karl Friedrich Mohr, who made many important advances in the methodology of titration in the 19th century. Karl Friedrich Mohr (November 4, 1806 - September 28, 1879) was a German pharmacist famous for his early statement of the principle of conservation of energy. ...