Periodic Trends And The Relations On The Behavior Of Elemental Compounds Research Papers Examples
Atoms are every bit of you and everywhere in nature. From the food you eat and the air you breathe, atom s behaves as an everyday material you get to used consciously and unconsciously. Human intervention of nature has resulted many great things as well as the not-so-good things. This has enabled us study how things happens and explain the complexity of the designs of nature’s works and used it to our advancement and profit. Today, we are now capable of seeing things up to the atomic level. Scientist has been able to study the electrons, protons and neutrons. Many elements were discovered and characterized.
As many elements are being discovered as time progress, scientists have devised tools to easily understand and observed, if upon certain arrangement, they would make trends of these things. The most used tool today is the periodic table. The modern periodic table is a simple and concise tool that could show the details of elements (i.e. name, atomic mass, atomic weight, mass number etc.) It is also observed that the elements are positioned in such way that element’s characteristics follows certain order and trends. This is collectively called periodic trends. According to Zumdahl (2001, p. 580), the following characteristics: ionization energy, electron affinity and atomic radius. Some elements can be grouped due to their similar behavior. We will focused and study on the alkali metals which can be found on the first column on the left side of the periodic table.
The metals of Group 1A of the periodic table are known as alkali metals. This is composed of the following elements: Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs) and Francium (Fr). The exception on this group is hydrogen (H) since it behaves as a gas. The main explanation hydrogen’s non-metallic character is the atomic size and composition. Hydrogen has 1 proton and neutron bounded nucleus with 1 electron circling and on 1s valence shell. This causes the H atoms to be very small and tightly pack.
A video from Youtube briefly demonstrate the behavior of alkali metals. It showed the general metallic characteristics of these elements. Alkali metals are soft (can be sliced by a knife) and easily corroded upon exposure to air. They also react violently upon contact with water.
The fast reaction of these elements can be explained by their ionization energy. They have the smallest ionization energies of all the elements because of their 1s valence-shell electron configurations. This means that they readily lose this electron in chemical reactions to yield ions (McMurry p. 215). The easy corrosion of alkali metals demonstrates a chemical reaction occurring to the metals and air. The presence of water vapor and exposed alkali metal reacts to form salts. The reaction occurs fast since the metals easily donate the 1 electron on its outer valence shell. The reaction occurs quickly as it goes down the group. Electrons being donated becomes less bound to the nucleus due to the larger valence shell of heavier metals. Therefore, from the video Cesium can readily donates its free electron since its attraction from the nucleus of its atom are far lesser than sodium and lithium due to the greater distance cause by a larger valence shell. The video has showed also the increasing intensity of reaction of alkali metals as it goes down the group in the periodic table. The most violent reaction is from Cesium which already break the container upon dropping the metal on water. The increase in intensity as it goes down the group can be explained by their low ionization energy and increasing atomic sizes. Imagine a bomb, a small bomb can cause an annoying bomb and small damage but if a large bomb is present, the destruction it could bring is beyond that of a small bomb. This analogy works to the situation. Cesium was far destructive than lithium since it is a larger element, based on its atomic size, and they can readily react/oxidize with water. Imagine what Francium could do upon subjecting it to the same scenario.
Ebbing, Darrel B. and Gamment, Steven D. General Chemistry 9th edition.New York: Houghton Mifflin Company, 2011. couver: UBC Press, 2009. 1-11. Print. p. 867-883.
McMurry, John E. Chemistry 6th edition. United States: Prentice Hall, 2011. Print. p. 210-222.
Zumdahl, Steven S. Chemical Principles 6th edition. New York: Houghton Mifflin Company, 2009. Print p. 570-590.