What are acids made of?

As Acids (English acid) is the name given to chemical compounds with a pH value of less than seven. Acids act as so-called Proton donors, that is, they have hydrogen ions (H.+) can be transferred to their reaction partner. The counterpart to acids are bases, also known under the term lyes.

Acids are very corrosive, depending on their concentration. Therefore, you must never work without suitable protective goggles. If necessary, protective clothing and protective gloves can also be useful. Should the acid come into contact with your hands, wash immediately with water. The instructions of the experimenter / teacher must be followed.
When dealing with acidic liquids, an important donkey's bridge has been established: 'First the water, then the acid, otherwise the monstrous happens'. Water must never be added to an acid, e.g. for the purpose of dilution. The abruptly released hydration energy causes the acid to evaporate and spray. That's why acids are always added to the water. The subsequent reaction is no less exothermic, but the energy released is evenly distributed over the surrounding water.
The motto is also available in English: Always do things as you oughta, add the acid to the water!