Alkali metal

Group	1
Period
2	3 Li
3	11 Na
4	19 K
5	37 Rb
6	55 Cs
7	87 Fr

The alkali metals share many characteristics. First they share the characteristic of being soft and silvery in color. And each of the elements in the alkali group has one positive charge in the outer shell. And all of these elements are very reactive the most is the Francium and the least is Lithium.[1] Alkali metals react violently with water and they even react when they come in contact with air. Alkali metals form ionic bonds with nonmetals.

Periodic table of elements with the Alkali Metals illustrated by black border.

Alkali metals share the characteristic of being malleable, ductile, good conductors of heat and electricity. Cesium and Francium are most reactive. All can explode in water, all Alkali dissolve in liquid ammonia K (s) + NH3 (l) → K+ (aq) + e- (aq). [2]

Lithium

Lithium Shells

Lithium Sample

Lithium reacting with water

Lithium oxide, a lithium compound flame test

Lithium burning

Properties

Lithium is a reactive metal. It is the least reactive alkali metals. Lithium reacts with water to make hydrogen gas and lithium hydroxide. Lithium is not found as a metal in the ground. It turns black when it is in air for a few seconds, then decays into a white powder after sitting in air for a few hours. Lithium burns with a crimson color at first, then the flame becomes bright silver-white; it burns at 1615 K, (1342 °C, 2448 °F). Lithium compounds make a crimson flame when heated. Lithium is soft; it is so soft you can cut it with a knife. Lithium is also very light; it is only half as heavy as water. It is the lightest metal. Lithium is the thirty-first most abundant element on earth. Lithium is almost always found in igneous rocks and in brines. Lithium sells for about $43 per pound.

Uses

Lithium has many uses but two of its main uses are in batteries (lithium batteries and lithium ion batteries) and in lithium pharmacology. Normal dry cell batteries have an average voltage of 1.5 volts. Lithium batteries have a voltage of 3.0 volts and lithium ion batteries have a voltage of about 3.7 volts. Lithium ion batteries are lighter and have a higher charge of twice the amount of the standard battery. Then there is the use in the medical field. The main use is in the treatment of bipolar disorder, and in the treatment of mania and depression.

History

Lithium was first discovered by Jose Bonifacio de Andrade e Silva in the 1700’s. Lithium was first isolated in the 1818 by William Thomas Brande and Sir Humphry Davy by using electrolysis.

Sodium

Sodium Shells

Sodium Sample

Sodium has an atomic number of 11, the Atomic symbol is Na, and the atomic mass is 22.9898 g/mol. [3] The word Sodium comes from the Latin word natrium. [4]

Properties

Sodium is one of the most reactive elements. When it comes in contact with water it starts to fizz and can some times burst in flames. Sodium will also tarnish when it comes in contact with air. Sodium is a soft metal that has a silvery metal color to it. Sodium like most other alkali metals in that it is light and it floats in water. Sodium is found on earth in great amounts but not normal in its pure form.

Uses

Sodium does not have a lot of uses by it self but when mixed with other compounds it can make zirconium and potassium. Sodium can also be used to improve the structure of alloys. Sodium are also use in a lot of cleaning soaps. Sodium is also used in agriculture, photograph and the medicine.[5] History Sodium was first isolated by Sir Humphry Davy in 1807. Its first use was as medical for headaches in medieval Europe.[6]

Potassium

Potassium Shells

Potassium Sample

Potassium has an atomic number of 19, the Atomic symbol is k, and the atomic mass is 39.0983 g•mol. The word Potassium comes from the word potash.

Properties

Potassium is a soft metal just like lithium you are able to use through it with a knife. It is also very reactive, when it comes in contact with water it will start to bur and when it comes in contact with air it tarnishes. Potassium has a natural silvery white color when it is in its natural stat but when brought to the out side element it is a dark gray. Potassium is also know as the element of all living things. Potassium is also the second less dense element, it floats on water.

Uses

Potassium is used in any thing but it most common and most effect application it is fertilizer. Potassium is also used in the making of gun powder and a alternative for table salt. History Potassium was first discover by Sir Humphry Davy in 1807. [7]

Rubidium

Rubidium Shells

Rubidium Sample

Rubidium has an atomic number of 37, the atomic symbol is Rb, and the atomic mass is 85.4678)  g•mol−1

Properties

Rubidium is the second most electropositive of the stable Alkaline elements. Rubidium is also very light it can float on water. Rubidium is also very reactive, it reacts when it comes in contact with water. Rubidium forms alloys with Mercury, cesium, and gold. Rubidium is grey white.

Uses

Rubidium is mostly used in ionized engines.

History

Rubidium was first discovered by Robert Bunsen and Gustav Kirchhoff in a mineral lepidolite in the 1860’s

Caesium

Caesium Shells

Caesium Sample

Caesium has an atomic number of 55, the atomic symbol is Cs. It melts at 28 °C

Properties

Caesium is the second lowest ionization potential. It is also the most stable out of the alkaline elements, as a solid it is a silvery gold. Caesium is a liquid at room tempters.

Uses

Caesium does not have many uses since it’s a liquid most of the time. Caesium is most commonly used in drilling ad in atomic clocks because of its extreme accuracy. Caesium is also use in biology and chemistry.

History

Caesium was discovered by Robert Bunsen and Gustva Kirchhoff in 1860 in mineral water.

Francium

Francium Shells

Francium has an atomic number of 87, the atomic symbol is Fr, and the atomic mass is 223  g•mol−1.

Properties

There is very little known about Francium it is the second rarest element. Francium is a metallic. There is around 320-550 grams in the world. Francium is the most reactive alkali metal.

Uses

No current use

History

Francium was first discovered by Marguerit Perey in 1939. Francium is the last element discovered in nature.

References

• Alkali metal by Wikipedia
• Lithium By Wikipedia
• Sodium by Wikipedia
• Potassium by Wikipedia
• Rubidium by Wikipedia
• Caesium by Wikipedia
• Franciumby Wikipedia