Strontium hydroxide
Encyclopedia
Strontium hydroxide, Sr(OH)2, is a caustic alkali
composed of one strontium
ion
and two hydroxide
ions. It is synthesized by combining a strontium salt with a strong base. Sr(OH)2 exists in anhydrous
, monohydrate
, or octahydrate form.
, drop by drop to a solution of any strontium salt, most commonly Sr(NO3)2 (strontium nitrate
). The Sr(OH)2 will precipitate out as a fine white powder. From here, the solution is filtered, and the Sr(OH)2 is washed with cold water and dried.
from strontium chloride
is undesirable. Strontium hydroxide absorbs carbon dioxide
from the air to form strontium carbonate
.
Alkali
In chemistry, an alkali is a basic, ionic salt of an alkali metal or alkaline earth metal element. Some authors also define an alkali as a base that dissolves in water. A solution of a soluble base has a pH greater than 7. The adjective alkaline is commonly used in English as a synonym for base,...
composed of one strontium
Strontium
Strontium is a chemical element with the symbol Sr and the atomic number 38. An alkaline earth metal, strontium is a soft silver-white or yellowish metallic element that is highly reactive chemically. The metal turns yellow when exposed to air. It occurs naturally in the minerals celestine and...
ion
Ion
An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...
and two hydroxide
Hydroxide
Hydroxide is a diatomic anion with chemical formula OH−. It consists of an oxygen and a hydrogen atom held together by a covalent bond, and carrying a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, as a ligand, a nucleophile, and a...
ions. It is synthesized by combining a strontium salt with a strong base. Sr(OH)2 exists in anhydrous
Anhydrous
As a general term, a substance is said to be anhydrous if it contains no water. The way of achieving the anhydrous form differs from one substance to another...
, monohydrate
Hydrate
Hydrate is a term used in inorganic chemistry and organic chemistry to indicate that a substance contains water. The chemical state of the water varies widely between hydrates, some of which were so labeled before their chemical structure was understood....
, or octahydrate form.
Preparation
Because Sr(OH)2 is very slightly soluble in water, its preparation can be easily carried out by the addition of a strong base such as NaOH or KOHPotassium hydroxide
Potassium hydroxide is an inorganic compound with the formula KOH, commonly called caustic potash.Along with sodium hydroxide , this colorless solid is a prototypical strong base. It has many industrial and niche applications. Most applications exploit its reactivity toward acids and its corrosive...
, drop by drop to a solution of any strontium salt, most commonly Sr(NO3)2 (strontium nitrate
Strontium nitrate
Strontium nitrate is an inorganic compound with the formula Sr2. This colourless solid is used as an colorant in pyrotechnics.- Preparation:Strontium nitrate is typically generated by the reaction of nitric acid on strontium carbonate.....
). The Sr(OH)2 will precipitate out as a fine white powder. From here, the solution is filtered, and the Sr(OH)2 is washed with cold water and dried.
Applications
Strontium hydroxide is used chiefly in the refining of beet sugar and as a stabilizer in plastic. It may be used as a source of strontium ions when the chlorineChlorine
Chlorine is the chemical element with atomic number 17 and symbol Cl. It is the second lightest halogen, found in the periodic table in group 17. The element forms diatomic molecules under standard conditions, called dichlorine...
from strontium chloride
Strontium chloride
Strontium chloride is a salt of strontium and chloride. It is a typical salt, forming neutral aqueous solutions. Like all compounds of Sr, this salt emits a bright red colour in a flame; in fact is used as a source of redness in fireworks...
is undesirable. Strontium hydroxide absorbs carbon dioxide
Carbon dioxide
Carbon dioxide is a naturally occurring chemical compound composed of two oxygen atoms covalently bonded to a single carbon atom...
from the air to form strontium carbonate
Strontium carbonate
Strontium carbonate is the carbonate salt of strontium that has the appearance of a white or grey powder. It occurs in nature as the mineral strontianite.- Chemical properties :...
.
Safety
Strontium hydroxide is a severe skin, eye and respiratory irritant. It is harmful if swallowed.External links
- http://www.chemicalland21.com/industrialchem/inorganic/STRONTIUM%20HYDROXIDE.htm