You have seen the perodic table in your chemistry class, studied the symbols of the elements, and probably used the numbers in some claculations. But what exactly are the elements of the Periodic Table? In this section, we will study the elements known as the representative metals, which make up the first two families of the perodic table.
Many properties of metals are attributed to the way their atoms are bonded. Each metal has electrons that when the right conditions exist, could move up to empty enery levels. A small amount of enery is required to move these electrons to the empty enery levels that each metal atom possess. Similarily, a small loss in energy could easily drop the upgraded electron to its former enery leverl. These properties account for the metallic bonds between metal atoms. Metallic bonds result from the easy flow of electrons between the closely spaced enery levels of metal atoms. Therefore each metal atom is bonded to a sea of electrons.
Also, the flow of electrons around the metal atoms give the properties of malleability (the ability of a metal to be shaped without breaking) and ductility ( the ability of metal to be drawn into a wire.) The metal atoms can withstand the stress of being moved against each other since they have electrons in common.
Alkali Metals make up the first family of the perodic table. Lithium and sodium are some examples. The alkali metals tend to give up one electron in a chemical compound. This accounts for their high reactivity with out elements. Therefore they are not found in nature, and difficult to obtain in their pure form. They react with air, water, and other substances.
The properties that make the alkali metals disguish from other families in the periodic table is that they are soft, have many metallic properties, are soft enough to be cut with a knife, are soluble in water, can conduct heat and electricity, and the solutions of these elements are colorless. Also, the alkali metals react vigorously in water.Sodium Reacts Violently With Water Lab For example, the reaction between water and sodium produces sodium hydroxide, hydrogen gas, and a good deal of energy. Also, the name of this family comes from the properties of alkali metals to form hydroxides with water. Compounds containing hydroxide is alkali or is basic.
Alkali earth metals make up the second family of the perodic table. Calcium and barium are some examples. The alkali earth metals also called alkaline earth metals usually give up two electrons in a chemical compound. However, like alkai metals, they are too reactive to be found in their pure state in nature. Alkali earth metals are also denser and not as soft as alkali metals.
Magnesium, an alkali earth metal, can be used as a firework. When exposed to a flame, magnesium produces a bright white light.
Aluminum is the third most abundant element in the Earth's crust and usually is found combined with oxygen. Alumiun yields three electrons in a compound. Aluminum was once more expensive that gold or silver. This was due to fact that it was difficult to extract in its pure form. In the late nineteenth century, better processes were developed, making it cheaper. Alumium is a good electrical conducter, highly reactive, can form lightwieght alloys, and is malleable.
Aluminum
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