Alkali metal is the name given to denote a group of elements that share some similar properties. The elements in the Group 1 of the periodic table are called alkali metals. Al these elements are extremely reactive and because of this, they are not found in their free from in nature. These elements are known to have low melting points as well as densities. They form very strong bases when the react with water and produce salts when reacting with halogens. They have very low ionization potentials. The elements considered to be alkali metals are Lithium, sodium, potassium, Rubidium, Cesium and Francium.
All have just one electron in their outer shells, making them very reactive. Low melting points (for metals, anyway) Likewise, low boiling points Conduct electricity and heat None are found in their elemental forms (i.e. They're always in compounds, you won't dig a lump of pure potassium out of the ground) All react with water to produce an alkaline solution and hydrogen gas They get more reactive as you go down the group Low density Soft (lithium is the hardest and it can still be cut with a knife without much trouble)
They are very reactive. They all have one valence electron.the futher down you look in the group, the more reactive is the element that come next. They all tend to form positive ion and when they form ion, the ion are always smaller then the parent atom.
Density of alkali metals is always lower than other metals and they also have one valence electron that is loosely bounded. For more information you can click the following given link.
There are eight groups of the periodic table. The first, Group I, contains the alkali metals. These are lithium, sodium, potassium, rubidium, caesium and francium. These elements are very reactive and become more reactive down the group: rubidium is therefore much more reactive than lithium.
All the elements in the alkali metal group are metals, but they are not the typical shiny sort that we would use as jewellery and for building cars. All are soft and can be cut by a knife and only shine a little when freshly sliced. All react violently with water. Lithium floats on water and fizzes a bit, sodium fizzes more and potassium charges around the surface of the water and bursts into flames. Rubidium and caesium explode with great force and the final element, francium is too dangerously unstable and radioactive to put any where near water.
The alkali metals form useful compounds called salts when they react with elements in Group VII of the periodic table ~ the halogens. For example, when sodium, the alkali metal reactions with the halogen chlorine, the result is sodium chloride ~ table salt.
Alkali metals can be defined as the group found in the first column of the periodic table. These are the chemical elements that are collectively known as alkali metals. They are –
The common feature associated with these metals is the similar structure of their electron in their outer orbit. They have somewhat same physical property. All of them are soft enough and can be cut by using knife. Most of the alkali metals are white in colour. However, caesium is of yellowish-white colour. Those metals have almost same chemical property as well. All of them react with water and produce hydrogen gas and metal hydroxide. Also they react with oxygen to produce oxide, peroxide or super-oxide depending on the type of the metal. Another significant and interesting feature of alkali metals is their illumination colour when they are burned in flame. The colour that is seen while placed in flame as follows –
Lithium – bright red Sodium – intense yellow Potassium – violet Rubidium – dark red Caesium – light blue
Group 1: The Alkali metals Elements in the group 1 (which all have one electron in their outermost shell) become more reactive as we go down the group. This is becasue the outermost electron shell gets further away from the influences of the nucleus, meaning the electron is more easily lost.
