Vinegar and Acetic Acid

The aerobic bacterial oxidation (by the genus Acetobacter) of alcohol to dilute acetic acid (8 %) is another ancient procedure, furnishing vinegar, a flavored acetic acid solution, fermented from wine, either, malt, or dilute alcohol. If pure dilute alcohol is fermented, pure dilute acetic acid results. The yield is 80 to 90% of theory. Air must be supplied, as these formulations indicate:

2 C₂H₅OH + O₂ -------- 2 CH₂CHO + 2 H2O
2 CH₃CHO + O₂ ------- 2 CH₃COOH

Since these reaction are exothermic, the alcohol can be slowly trickled through either the apparatus, letting the heat dissipate, or it can be recirculated with special cooling. It cider, malt, or wine is fermented, the acetic acid content of the resulting vinegar rarely exceeds 5 % because of limitations of the sugar content: if dilute alcohol is the raw material, the acetic acid may rise to 12 or 14% at which acidity the bacteria cease to thrive. If a fruit juice is turned to vinegar, certain eaters are formed, varying with the raw material and thus imparting a characteristic flavor. Synthetic acetic acid is made from ethylene, or by treating methanol with carbon monoxide.

Glyserin as Medicine

Glycerin is a clear include as organic chemicals, nearly colorless liquid having a sweet taste but no odor. Scheele first prepared glycerin in 1779 by heating a mixture of olive oil and litharge. On washing with water, a sweat solution was obtained, giving, on evaporation of the water, a viscose heavy liquid, which the discover called “the sweet principle of facts.” In 1846 Sobrero produced the explosive nitroglycerin for the first time, and in 1868 Nobel, by absorbing it in keselghr, made it safe to handle as dynamite. These discoveries increased the demand for glycerin. This was in part satisfied by the development in 1870 of a method for recovering glycerin and salt from spent soap lyes. Since about 1948, glycerol has been produced from petrochemical raw materials by synthetic processes.

As chemical glycerin have many function can use, glycerin can use as medicine like for lips swelling or glycerin can also use as explosive material like as on nitroglycerin that can be convert to a very explosive material.

Super glue and Power glue

Super glue and Power glue often sell in different name but actually have the same function. Superglue actually have a chemical name cyanoacrylate adhesive that have a chemical formula of methyl-2-cyanoacrylate or ethyl-2-cyanoacrylate. Superglue and powerglue may differ from substance that bond on cyanoacrylate, methyl or ethyl.

This adhesive have many purpose function beside cause have a very fast bonding effect on both material that stick to. Not like many other material that just stick for certain material like just for paper or just for wood or just for plastic. Power glue can stick of many materials; plastic, wood, metal, and glass.

Some point that is not good enough bonding if gluing of porous materials or hard and smooth material like glass. For gluing some of those materials we must add some filler or strengthen material like fiber. For those uses and function can see the detail on Superglue and Powerglue.