Hydrometer
Hydrometer, device for measuring some characteristics of a liquid, such as its density (weight per unit volume) or specific gravity (weight per unit volume compared with water).
The device consists essentially of a weighted, sealed, long-necked glass bulb that is immersed in the liquid being measured; the depth of flotation gives an indication of liquid density, and the neck can be calibrated to read density, specific gravity, or some other related characteristic.
`text(Principle Operation of the hydrometer)` is based on [Archimedes' principle] that a solid suspended in a fluid is buoyed by a force equal to the weight of the fluid displaced by the submerged part of the suspended solid. Thus, the lower the density of the substance, the farther the hydrometer sinks. Thus, it is based on the principle of `text(flotation)`.
`text(Ranges :)`
In low-density liquids such as kerosene, gasoline, and alcohol, the hydrometer sinks deeper, and in high-density liquids such as brine, milk, and acids it doesn't sink so far.
In fact, it is usual to have two separate instruments, one for heavy liquids, on which the mark 1.000 for water is near the top of the stem, and one for light liquids, on which the mark 1.000 is near the bottom.
In many industries a set of hydrometers is used - covering specific gravity ranges of 1.0–0.95, 0.95–0.9 etc. - to provide more precise measurements.
`text(Scales :)`
Modern hydrometers usually measure specific gravity but different scales were (and sometimes still are) used in certain industries. Examples include:
`=>` `text(API gravity)-` petroleum industry.
`=>` `text(Baumé scale)-` formerly used in industrial chemistry and pharmacology
`=>` `text(Brix scale)-` fruit juice, wine making and the sugar industry
`=>` `text(Plato scale)-` primarily used in brewing
`=>` `text(Twaddell scale)-` formerly used in the bleaching and dyeing industries
`text(Specialized hydrometers :)`
`text(Lactometer)->` Purity of cow's milk
`text(Alcoholmeter)->` Indicates the alcoholic strength of liquids
`text(Saccharometer)->` Used for determining the amount of sugar in a solution
`text(Thermohydrometer)->` For measuring the density of petroleum products
`text(Urinometer)->` Designed for urinalysis
`text(Barkometer)->` A barkometer is calibrated to test the strength of tanning liquors used in tanning leather
`text(Acidometer)->` Measure the specific gravity of an acid
The device consists essentially of a weighted, sealed, long-necked glass bulb that is immersed in the liquid being measured; the depth of flotation gives an indication of liquid density, and the neck can be calibrated to read density, specific gravity, or some other related characteristic.
`text(Principle Operation of the hydrometer)` is based on [Archimedes' principle] that a solid suspended in a fluid is buoyed by a force equal to the weight of the fluid displaced by the submerged part of the suspended solid. Thus, the lower the density of the substance, the farther the hydrometer sinks. Thus, it is based on the principle of `text(flotation)`.
`text(Ranges :)`
In low-density liquids such as kerosene, gasoline, and alcohol, the hydrometer sinks deeper, and in high-density liquids such as brine, milk, and acids it doesn't sink so far.
In fact, it is usual to have two separate instruments, one for heavy liquids, on which the mark 1.000 for water is near the top of the stem, and one for light liquids, on which the mark 1.000 is near the bottom.
In many industries a set of hydrometers is used - covering specific gravity ranges of 1.0–0.95, 0.95–0.9 etc. - to provide more precise measurements.
`text(Scales :)`
Modern hydrometers usually measure specific gravity but different scales were (and sometimes still are) used in certain industries. Examples include:
`=>` `text(API gravity)-` petroleum industry.
`=>` `text(Baumé scale)-` formerly used in industrial chemistry and pharmacology
`=>` `text(Brix scale)-` fruit juice, wine making and the sugar industry
`=>` `text(Plato scale)-` primarily used in brewing
`=>` `text(Twaddell scale)-` formerly used in the bleaching and dyeing industries
`text(Specialized hydrometers :)`
`text(Lactometer)->` Purity of cow's milk
`text(Alcoholmeter)->` Indicates the alcoholic strength of liquids
`text(Saccharometer)->` Used for determining the amount of sugar in a solution
`text(Thermohydrometer)->` For measuring the density of petroleum products
`text(Urinometer)->` Designed for urinalysis
`text(Barkometer)->` A barkometer is calibrated to test the strength of tanning liquors used in tanning leather
`text(Acidometer)->` Measure the specific gravity of an acid