The elements that are situated in group 1 and group 2 are called ‘Alkali metal’. There are generally two types of alkali metals. The element that exists with one electron in their valence shell is called the alkali metals element, and the element, which consists of two electrons  in its s-subshell , is called alkaline earth metals . S-Block generally consists of 14 elements that are- hydrogen, sodium, beryllium, magnesium, rubidium, caesium, helium, calcium, potassium, radium, francium, lithium, barium, and caesium. The alkali metals are used in the various fields associated with medical, biological, agricultural and industrial fields. The general characteristic of the alkali metals depends on the variety of the different metals.

Alkali metals: general characteristics

The general characteristics of the alkali metals focus on both the physical and chemical attributes. Some major characteristics of Alkali metals are –

•  Alkali metals can be found in column 1A in the periodic table.
• These metals can be easily ionized.
• Alkali metals are generally silver in colour, soft and dense in quality. 
• These metals generally have a very low melting point’.
• All the metals that exist in the alkali group of metals are incredibly reactive.
• These metals generally have low ‘electron affinities’.
• These metals generally have low electro-negativity.

S-block elements: characteristic attributes

There are some general characteristics of alkali metals. The characteristics of the S-block elements are further divided into two qualities that are physical and chemical. 

• Electronic configuration: Alkali metals are block elements because they have an electron on their outermost side.

• Large atomic radii: Alkali radii presented in the alkali metals are the largest in their respective period. This further increases when one travels from group Li to Cs in the periodic table.

• Alkali myrtles generally have unipositive ions: The alkali metals generally have their oxidation state of +1 in their substance and are highly electropositive in nature. 

There are some chemical qualities are there in the alkali metals they are –

• These metals are highly reactive to the water: These metals react with water and form dihydrogen and hydroxide. It further includes that lithium is less reactive to the water as compared to the other group of metals. Other metals in this group react excessively in water. These are one of the major characteristics of alkali metals.

• Alkali metals reducing nature: Alkali metals generally have dynamic reducing agents. In this context, lithium has a high reducing nature, and sodium has a low, reducing nature. The potential of the standard electrode measures the reducing power of the metals, which is the general characteristic of alkali metals.

• The reaction of the alkali metals in the solution of liquid ammonia: The alkali metals have the tendency to dissolve in the liquid form of ammonia. It forms a blue colour after dissolving in the solution of liquid ammonia.

Formation of salt in the alkali metal

Alkali metals displace hydrogen from acids and corresponding salts. Alkali metals displace hydrogen from the acid because they contain only one electron in their outermost shell. Alkali metals existed below the level of hydrogen. Especially the metals that are placed above hydrogen in the context of reactivity displace hydrogen from the acid, but those metals that exist below the hydrogen, do not displace hydrogen from acid.

Conclusion 

Alkali metals are very important in the field of chemistry. The group of metals includes various uses in various fields of life. The example of lithium can be mentioned. Lithium is used as a drug that stabilizes the mood. Lithium is also used as a working for the glasses and ceramics. Lithium-6 is used mainly in the production of tritium. Sodium is used in the field of textile, paper, chemical and petroleum industries. Sodium hydroxide is used in the cleansing of the oven. Potassium chloride has an important role in the growth of the plants. Potassium is further used as a fertilizer in agricultural fields. The vapour of rubidium is generally used for laser cooling.