Abdulaziz Khalid Al- Kuwari 8C.
Abdulaziz Khalid Al-Kuwari
This is the periodic table of elements which consists of alkali (reactive) metals, alkali earth metals, transition metals, poor metals, rare earth metals, non-metals, noble gases and Hydrogen. I will research the first column on the left excluding hydrogen. I will explain how the reactivity of those metals relate to when they were discovered. As they go down, they have a higher atomic number which causes them to be more reactive.
Discovery: The first indication about the presence of Lithium came to light in 1800, by Brazilian scientist and a statesman, who, during a trip to the Scand avian countryside chanced upon a previously unknown mineral, which he decided to call Petalite. Compounds that contain Lithium are initially changed to Lithium chloride (LC) An electrical is made to run through the melted lithium chloride, which is basically responsible for isolating lithium from chlorine gas.
Properties: Although Lithium is considered to be an active element, there are other alkali metals that are said to more active. At higher temperatures its reaction to water is greater than at room temperature. There is also a noticeable reaction with most acids that give off hydrogen gas. Although, there is no active reaction in Lithium with oxygen at normal temperature, but when Lithium is heated at more than 100’c it forms lithium oxide (Li20).
Uses: Lithium is an important ingredient in the production of aluminum, but its importance in the manufacturing of glass and ceramics cannot be over looked. A very small addition of Lithium Carbonate (Li2CO) when added to ceramic or glass strengthens both these materials significantly. Shock resistant cookware (such as the Pyrex Brand) and black and white television tubes are prime examples of the important use of Lithium in these products. A very high percentage of Lithium, as much as 40% used in the United States goes into the manufacture of these products. 
Discovery: Sodium carbonate or soda (Na2CO2) is termed the sodium compound that was very well known even in ancient times. Because sodium is very common, it explains the reason that glass was one of the earliest chemical products made by humans. The heating of sodium carbonate and calcium mixed together makes glass. When this mixture cools down, the result is the clear, hard transparent chemical product known as glass. The Egyptians were manufacturing large quantities of glass around 1370 B.C. The Egyptians called this mixture soda patron. Later on the Romans used a similar term for this compound. The Romans called it natrium. These pre-historic names explain the chemical symbols that were later used for sodium, Na.
Extraction: One method for getting pure sodium is by running an electrical current through the melted sodium chloride.The method is quite like the method that was used by Humphrey Davis in 1808. But the demand for sodium metal is not as much as the demand for Sodium compounds. Another similar method is used in producing Sodium hydroxide (NaOH). This sodium hydroxide acts as the base for producing other sodium compounds.
Properties: Sodium, when heated with the combination of oxygen at normal room temperature becomes very active, giving off a brilliant golden-yellow flame. Sodium when combined with water shows a very volatile reaction. (Refer to attached sidebar) Sodium is generally stored under kerosene or naphtha, liquids to which sodium has no positive reaction.
Uses: Because natural rubber is expensive as it is being made from the sap of rubber trees, Sodium is used in the manufacture of artificial rubber. A small molecule is basically the starting material for artificial rubber. Reacting with itself, the small molecule becomes bigger and is termed polymer. Artificial rubber is made from this polymer 
Discovery: Potash was known to primitive man. Potassium compound is formed by the burning of wood when these ashes were cleaned with water they become potash. Then the water was evaporated to produce potash, frequently called vegetable alkali.Theperson who invented the method of separating potash and ash into their natural form was Humphrey Davy. Instead of the traditional method of using water, he melted selected quantities of potash and soda, and introduced an electrical current through the melted substances. When he saw tiny droplets of metal liquid forming in this mixture, his surprise knew no bounds. This historical droplet of metal that formed in the cases was the first piece of potassium ever witnessed by man.OnOctober 6, 1980, Davy experienced his initial success with this method. After some days this experiment was carried out once more, using soda ash and produced sodium meta. Davy called these elements after their previous names, sodium for soda ash and potassium for potash.
Properties: Similar to other alkali metals, potassium reacts very violently when mixed with water, giving off hydrogen gas. This produces such intense heat that it ignites and may even explode. Floating potassium metal on water is definitely not recommended, as potassium would just skim through the surface of the water. This skipping is the result of hydrogen gas that is produced in the reaction which pushes the metal, and this could catch fire and result in an explosion.
Uses: Potassium can also be used as a heat exchange medium. A heat exchange material can be defined as one that gathers heat from one place and transfers it to another place. In this process heat is produced at the heart of the reactor. Potash (Potassium Chloride) is also commonly used as a fertilizer. 
Discovery: Using a spectroscope Bunsen and Kirchhoff discovered Rubidium from llllepidolite. A Jesuit priest, Abbey Nicolas Poda of Neuhaus discovered this mineral in the 1709’s. When Bunsen and Kirchhoff heated lepidolite, according to their report, they discovered two new lines in the spectrum. The brilliant red color of the recently discovered alkali metal, were instrumental in giving this new element and the symbol RD from rubidus, which the ancients associated with the deepest red.
Properties: Rubidium has a melting point of 39’C (102F), possessing a boiling point of 688’C (1,270F) and is a soft, silvery metal.Rubidiumis amongst the most active of elements. It bursts into flame when exposed to the oxygen in the air. Therefore it is stored submerged in kerosene, Rubidium produces hydrogen when exposed to water, and it can also burst into flames. Rubidium also reacts violently when exposed to the halogens (fluorine, chlorine, bromine and iodine) Atomic clock are made using Rubidium, but these are very special clocks, and are used in extremely special purpose, where extremely precise time keeping is essential.
Uses: A photocell is basically a device that converts energy into light; although, Rubidium is used for other types of alkali metal are still preferred. One use of a photocell is in security alarms, where it is used a motion detector. A ray of light is given off by a special device, which produces an electric current. If anything breaks this beam of light, the current is suspended resulting in the sounding of the alarm. 
Discovery: Cesium was discovered in a similar manner. While studying a sample of water in 1859 that was drawn from a spring Bunsen and Kirchhoff observed minute spectral lines of sodium, potassium, lithium, calcium and strontium, elements that were previously well known. After removing all these elements from the spring water, Bunsen and Kirchhoff were intrigued to find two lovely blue lines in the spectrum of the “empty” spring water. For quite some time, the name of Cesium was spelled as caesius.Thereare basically two methods for obtaining Cesium in its purest form. In the first method, calcium is mixed with molten (melted) cesium chloride:Theother method used is to cause an electric current to run through a melted or molten cesium compound.
Properties: Cesium reacts immediately with the oxygen in the air, and also is considered to be very volatile when exposed to water, because the hydrogen gas that is released bursts instantly into flames, because of the fierce heat generated by the reaction. Some mineral liquid, like kerosene or some other mineral oil must be used to store kerosene, to prevent it from reacting with the oxygen and the molecules of water present in the air. Other elements that trigger an intense reaction from Cesium are acids, halogens, sulphur and phosphorus.
Uses: Cesium does not have very extensive uses. It is primarily a getter in light bulbs, because it gets the gases out of the bulb as the bulb must not have any gases to function properly. Minute quantities of Cesium react with any air that is present in the bulb.Cesiumis also widely used in the manufacture of photo electric cells. These Photoelectric cells are devices for converting sunlight into electrical energy. However, an atomic clock is considered to be the most precise instrument that utilizes Cesium, enabling it to give very precise time always. 
Francium is not obtained from the surface of the Earth. Francium was discovered by a French physicist Marguerite Perry, who had a great passion for science even at a very young age. Because of the early death of her father, she could not afford to attend a university. Therefore, she began working with the Radium institute in Paris, which had been founded by Marie Cure (1867-1934), and her renowned scientist husband, Pierre Cure (1859-1906) for the sole purpose of studying radioactive material. 
Up to 1700, very few elements were known to man. Gold and silver were amongst the few known elements because they could be used without any special refining process. However, Iron has been in use since very early times by humans, mainly because its prime property iron oxide (rust) is easily reduced by removing the oxygen, and reintroducing electrons previously removed thereby making pure iron. In the period referred to as the iron age, crude smelters were in use The smelter basically used , mineral rust heated with Soot which is really carbon, The carbon was heated thereby forming the purest form of iron. Carbon and some other atoms mix together to produce a mix of carbon monoxide and carbon dioxide.
It sets a person wondering as to what does this have to with your question. The association that is being discussed is connected with the reaction of this metal because it basically rules the method whereby you discover the element and the problems associated with separating it into its individual atoms.
Initially precious metals that would react were discovered, and then the ways and means to produce it in its purest forms were introduced. This is basically due to advances in science and technology that is easily available to those who need it. In retrospect, after chemistry progressed in leaps and bounds, and invented tools that could separate and analyze elements and could be obtained and used by everyone. Therefore the reaction of these elements, and the day and period of their discovery is quite significant.