Alkali metals

Alkali metals are known as elements of the first group in the periodic table, except hydrogen, which includes lithium (Li), sodium (Na), potassium (K), rubidium (Rb), cesium (Cs) and francium (Fr). The characteristics of alkali metals include:

Since these metals are alkali metals when they interact with water, the hydrogen atom separates into the water molecule to form hydrogen, while the other hydrogen atom bonds with oxygen to form hydroxide.
All the elements of the first group in the periodic table have a valence electron, and the electronic distribution has s1, which means that it participates in chemical reactions.
The alkali metals are bright, soft enough to cut the knife, and generally, have a white color, but cesium is a yellowish-white color, and when placed in the flame, most of them give distinctive colors, for example, lithium shines bright red, and sodium appears yellow. The heated potassium gives violet, dark red and light blue cesium rubidium, so it is possible to differentiate these metals according to the colors they produce when they are heated.
Sodium is the sixth most abundant element on Earth (2.6%), potassium is the seventh (2.4%), lithium and rubidium are considerably less abundant, and cesium is a very rare element. With very small amounts of uranium minerals. chemistry analysis 
Alkali metals are highly reactive elements, so they are found in nature with other elements, and some simple minerals that contain them such as halite (sodium chloride), sulfite (potassium chloride) and carnalite (potassium chloride, chloride magnesium) dissolve in water. , making metals easy to extract and purify, but complex and water-insoluble minerals are more abundant in the earth's crust.
Alkali metals react easily with oxygen and water vapor in the atmosphere (lithium also reacts with atmospheric nitrogen), react strongly, often violently with water to produce hydrogen, form strong caustic solutions and react with non-material. most common metallic such as halogens and sulfur. Halogens and phosphorus also interact with many organic compounds, especially those that contain halogen, or a hydrogen atom that is easy to replace.
Alkali metals tend to form positively charged ions (cations) when they interact with nonmetals, resulting in the production of highly meltable compounds, which are solid crystals that are interconnected by ionic bonds that result from the forces of mutual attraction between charges. positive and negative electrical.