Hydrometers
These instruments are used to determine, usually by direct reading from a graduated rod, the specific gravity of solids and liquids or some arbitrary quantity related to specific gravity (e.g., alcohol concentration). Readings are sometimes converted via tables into other units.
The aforementioned instruments are typically made of glass (although some may be made of metal, e.g., German silver, silver, etc.) and loaded from one end with a portion of mercury or fine lead shot. These weights are usually fixed, but instruments for determining the density of liquids with different specific gravities sometimes
are designed so that these weights can be changed or additional ones added. Some hydrometers (for example, those used to determine the concentration of acid in batteries) are enclosed in a glass syringe. Other types of instruments are combined with a thermometer
Source: "Explanations to the Harmonized System of Foreign Trade of the Russian Federation (HS Code of Russia)" (prepared by the Federal Customs Service of Russia) (volume 4, sections XVI - XXI, groups 85 - 97)
Морфология
Род
Понятие «ареометры» мужского рода.
Склонение и число
| Падеж | Единственное число | Множественное число |
|---|---|---|
| Р | ареометра | ареометров |
| Д | ареометру | ареометрам |
| В | ареометр | ареометры |
| Т | ареометром | ареометрами |
| П | ареометре | ареометрах |