Understanding The Periodic Table - Research Paper Example

? UNDERSTANDING THE PERIODIC TABLE Your Full The Periodic table of elements is one of the tools in chemistry that plays a significant role in understanding the behavior of all the known elements. It provides useful information on the size of the atom of the element, its natural state at room temperature and its physical properties (Interactives, n.d.). This paper provides some basic information needed to understand the periodic table of elements. The Atom All matter is made up of very small particles called atoms. They are small, indivisible particles that cannot be seen by the naked eye. With the advancement of technology, atoms can now be viewed through scanning microscopes (Genesis, n.d.). Protons, electrons and neutrons are the particles that can be found in an atom. The image below is a representation of a simple atom. Figure 1. Image of a simple atom with its protons, neutrons and electrons (Source: education.jlab.org) Protons are positively charged particles, while the electron is negatively charged. Neutrons are uncharged particles (Genesis, n.d.). The mass of the atom is measured from the mass of the proton and neutron, and they are located at the center of the atom clumping together and called the nucleus. Protons weigh approximately 1.67 x 10-24 grams or 1 atomic mass unit (amu) and the neutron also weighs 1 atomic mass unit (Interactives, n.d.). As mentioned earlier, all elements are made up of atoms. The similarity of the elements and their differences are also characterized by the properties of the atoms. Periodicity Dmitri Mendeleev was the scientist who created the periodic table of elements. In 1868, he arranged the different known elements during his time in order of their mass. That time, there were only sixty elements, so it was not so difficult. He observed that there was a pattern of similarity in characteristics on the arranged elements. This pattern was referred to as periodicity. In 1913, a scientist named Henry Moseley rearranged Mendeleev’s table in order of the atomic number. The atomic number is the number of protons present in the atom. This new arrangement became the more acceptable version of the periodic table that we use until now (Interactives, n.d.). The Periodic Table of Elements The periodic table of elements displays several informations about a particular element. The blocks in the periodic table have the atomic symbol at the center of each block, usually in capitalized, larger, bold-faced fonts. The atomic symbol stands for the first letter of the English name of the element, or sometimes, its Latin name. If there are two letters, meaning there is already an existing element with the symbol of only the first letter, the second letter is already written in small case. Figure 2 shows a typical block of a periodic table. Figure 2. A Typical Block in the Periodic Table of Elements (Source: science.howstuffworks.com) Periodic tables have different designs in terms of the location of the information and the type of information placed on each block. Usually, they have an example of the block to identify the parts of the block, and legends to identify the metals, non-metals and transition metals. Colorful periodic tables are much easier to understand since the colors also serve as legends making it easier to identify the elements. The atomic symbol of gold, Au, is from its Latin name Aurium. The number at the upper center of the block is the atomic number, which is representative of the number of protons of an element (Genesis, n.d.). In this case, 79 is the atomic number of gold, which means that the element has 79 protons. The number at the lower center of the block is the atomic mass of gold. Some periodic tables also include other physical properties in the blocks such as the element’s specific gravity and melting point. Again, these can be identified using the sample diagram of the blocks in the periodic table. Groups and Periods Figure 3 is a simple representation of the modern periodic table of elements. As can be seen, the elements are arranged in terms of increasing atomic number, in this image, found at the upper left corner of each block. There are7 periods in the periodic table and the elements comprising the periods range from two to eighteen. Trend of the elements from left to right of a period shows the increase in the number of electrons, and a change in the chemical and physical properties of the elements (www.bbc.co.uk, n.d.). Looking at the periodic table, the arrangement of the elements from top to bottom are referred to as groups, while from left to right, they are referred to as periods. The modern periodic table is composed of 18 groups. Members in a similar group have physical and chemical characteristics that are similar with each other because they have almost the same number of outer electrons (Genesis, n.d.), or valence shell electrons. The separate period of the Figure 3. The Modern periodic table of elements (Source: http://www.aip.org/history/curie/periodic.htm.) lanthanides and actinides are not really separated from the periodic table. They are arranged as such to differentiate them from the rest of the metals since most of them are already synthetic or man-made. The first group, Group I are alkali metals, except hydrogen. They are referred to as such because of their high reactivity with water, forming alkaline or basic solutions. Going down that group, the metals become more and more reactive. Group 7 called halogens, are the elements which exist as diatomic molecules. They are also reactive, with fluorine being the most reactive, and iodine being the least. Bromine is one of the only two liquid elements in the periodic table. The noble gases, Group 0, are non-reactive gases, all members of this group are, as the name implies, all in the gaseous state at room temperature. The transition metals, found between groups 2 and 3, include iron, cobalt and copper. These metals are usually capable of forming complex ions and form colored compounds (www.bbc.co.uk, n.d.). References Genesis. (n.d.). The Periodic Table: Atoms, Elements and Isotopes. genesismission.jpl.nasa.gov/educate/scimodule/UnderElem/.../TeachText.pdf Interactives: The Periodic Table. (n.d.). Retrieved from www.learner.org/interactives/periodic/ Chemistry: Periodic Table. (n.d.). Retrieved from http://www.bbc.co.uk/bitesize/standard/chemistry/elementsandreactions/periodic/revision/1/ Read More