Methanol – it is methyl or wood alcohol, carbinol – has a chemical formula CH3OH. Appearance – the colourless transparent liquid which is perfectly mixing up with water. Well mixes up also with some organic matter. It is very poisonous. Intake even of small amounts of methanol can lead to a blindness, or a lethal outcome.
Instruction
1. The main modern way of receiving methanol – reaction of carbon monoxide (SO) with H2 hydrogen), at high temperatures and pressure, with use of zinc-copper catalysts.
2. There is very simple and evident high-quality reaction. The thin copper wire better twisted by "spiral" should be made red-hot, for example, in a flame of a spirit-lamp or the lighter and to lower quickly in a test tube or other small capacity, with the studied alcohol. The main thing – what at the same time will be a smell!
3. If smells of "rotten apples" - it sign of formation of ethyl aldehyde (acetic aldehyde), therefore, in a test tube there was an ethanol. If there is a pungent, unpleasant, "burning" smell – formaldehyde (ant aldehyde) so smells, therefore, in a test tube there was a methanol! Certainly, it is only a "rough" and not especially reliable method. Is more difficult, but and more sensitive.
4. For example, it is possible to carry out reaction of "unknown alcohol" with potassium permanganate in acidic environment. If at the same time formaldehyde is formed, it is found the subsequent reaction with fuksinosernisty acid. The painted connection is formed; extent of coloring demonstrates existence and initial concentration of methyl alcohol. It is an exact and highly sensitive method allows to find 0.05 mg of methanol.
5. Instead of fuksinosernisty acid, it is possible to use hromotropovy acid. It is even more sensitive method, but also more difficult, "whimsical", it allows to define about 0.001 mg of methanol. As presence of formaldehyde prevents methanol definition (unlike the last way).