Melam (chemistry)
Encyclopedia
Melam is a condensation product of melamine
Melamine
Melamine is an organic base and a trimer of cyanamide, with a 1,3,5-triazine skeleton. Like cyanamide, it contains 66% nitrogen by mass and, if mixed with resins, has fire retardant properties due to its release of nitrogen gas when burned or charred, and has several other industrial uses....

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Synthesis

Melam was discovered by Liebig in 1834 from the residue of heating ammonium thiocyanate
Ammonium thiocyanate
Ammonium thiocyanate is an inorganic compound with the formula NH4SCN. It is the salt of the ammonium cation and the thiocyanate anion.-Uses:...

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Chemical property

In the presence of 30% ammonia
Ammonia
Ammonia is a compound of nitrogen and hydrogen with the formula . It is a colourless gas with a characteristic pungent odour. Ammonia contributes significantly to the nutritional needs of terrestrial organisms by serving as a precursor to food and fertilizers. Ammonia, either directly or...

, melam undergoes hydrolysis to form ammeline
Ammeline
Ammeline is a triazine. It is the hydrolysis product of melamine.-Synthesis:Ammeline can be synthesized by the pyrolysis of urea, or the condensation reaction amond 2 moles of dicyandiamide with 1 mole of biuret....

 and melamine
Melamine
Melamine is an organic base and a trimer of cyanamide, with a 1,3,5-triazine skeleton. Like cyanamide, it contains 66% nitrogen by mass and, if mixed with resins, has fire retardant properties due to its release of nitrogen gas when burned or charred, and has several other industrial uses....

. It also reacts with concentrated nitric acid
Nitric acid
Nitric acid , also known as aqua fortis and spirit of nitre, is a highly corrosive and toxic strong acid.Colorless when pure, older samples tend to acquire a yellow cast due to the accumulation of oxides of nitrogen. If the solution contains more than 86% nitric acid, it is referred to as fuming...

, producing cyanuric acid
Cyanuric acid
Cyanuric acid or 1,3,5-triazine-2,4,6-triol is a chemical compound with the formula 3. Like many industrially useful chemicals, this triazine has many synonyms. This white, odorless solid finds use as a precursor or a component of bleaches, disinfectants, and herbicides...

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Upon heating, melam first loses ammonia to form melem
Melem
A heptazine, or tri-s-triazine or cyamelurine, is a type of chemical compound that consist of a planar triangular core group, C6N7, or three fused triazine rings, with three substituents at the corners of the triangle....

, and then melon.
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