Vinegar essence

Acetaldehyde is obtained by the catalytic hydration of acetylene or by the catalytic dehydrogenation of ethanol. Formic acid and formaldehyde are by-products of acetic acid synthesis. They are removed by distillation. Chemically pure acetic acid is diluted with water to 60-80% by volume to obtain the vinegar essence. The essence is a strongly corrosive liquid and is sold with special precautions. It is diluted further with water for production of food grade vinegar. 

Raucher-essenz, /. aromatic essence, fragrant essence, -essig, m. aromatic vinegar. rSucherig, a. smoky dingy. 

We know from the conservation of mass that when we run a reaction in a batch reactor the mass of products must be equal to the mass of reactants so long as nothing has escaped from the reactor. This holds absolutely and is independent of the chemical reaction type, mechanism, or stoichiometry. All that chemical reactions do is to rearrange the atoms and mass in the molecules. In essence the labels on the mass change but that is all. If the reaction in solution leads to a gas such as the reaction of baking soda with vinegar water (that is, sodium bicarbonate with dilute acetic acid), then a mass change can take place because one of the products is a gas and can escape the vessel ... 

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