Alkali metals - France, cesium, rubidium, potassium, sodium, lithium - so named because of the fact that the form of alkali by reaction with water.Due to the high ability to react these elements should be stored under a layer of mineral oil or kerosene.The most active of all these substances is considered to be France (has radioactivity).
Alkali metals - substances soft, silvery color.Freshly cut their surface has a characteristic luster.Alkali metals are melted and boil at low temperatures, have high thermal and electrical conductivity.They also have a low density.
chemical properties of alkali metals
substance is a strong reducing agents exhibit in the compounds of the oxidation state (only) one.With increasing atomic weight of the alkali metals increases and resilience.Virtually all of the compounds are soluble in water, they are ionic.
with moderate heating alkali metals ignite in air.In conjunction with the salt-forming agent hydrogen hydrides.The products of combustion are typically peroxides.
alkali metal oxides are yellow solids (oxides of rubidium and potassium), white (oxides of sodium and lithium) and orange (cesium oxide) colors.These oxides are capable of reacting with water, acids, oxygen, acid and amphoteric oxides.These basic characteristics are inherent in all of them and have a pronounced character.
peroxides of alkali metals - powder yellow-white color.They are capable of reacting with carbon dioxide and carbon monoxide gases, acids, nonmetals, water.
hydroxides of alkali metals are soluble in water, white solids.In these compounds are shown (bright enough) basic properties of alkali.From France to the power of lithium bases and solubility in water increases.Hydroxides considered strong enough electrolytes.They react with salts, amphoteric hydroxides and oxides, individual non-metals, acid oxides.Except for the lithium compound with all other exhibit thermal stability.Calcination of lithium hydroxide is its decomposition into water and oxides.These compounds are obtained by means of electrolysis of aqueous chloride solutions, a number of metabolic reactions.Hydroxides are also obtained by reacting components (or oxides) and water.
Almost all salts described metals (except for certain lithium salts) in water soluble good.Formed by weak acids, saline solutions have a reaction medium (alkaline) due to hydrolysis of the formed salt of the strong acids are not hydrolyzed.Common salt is the stone (table) salt, silicate glue (water glass), potassium nitrate, bertoletova salt, potassium permanganate, soda drinking soda ash and others.
All alkali metal compounds have the ability to change the color of the flame.It is used in chemical analysis.Thus, the flame carmine-red colored lithium ions in violet - potassium ions, in yellow - sodium, whitish-pink - rubidium, purple-red - cesium.
Due to the fact that all alkaline cells are the most powerful reducing agents, they can get by the electrolysis of salt melts.
The use of alkali metal
elements are used in different spheres of human activity.For example, cesium is used in solar cells.The bearing metal is used as catalyst lithium.Sodium is present in the discharge lamps, nuclear reactors as a coolant.The research activity is used rubidium.
