Assignments Essay

Choose one scientist involved in formulating the modern periodic shelve and describe why their twist made a probatory contribution to the development of the periodic table. Dmitri Mendeleevs contribution to the modern day periodic table is widely renowned in the report of chemical science. Mendeleev was the creator of the periodic table arranging 63 cognise elements in order of their atomic mass. His discovery made a significant impact in the development of the periodic table as it set the foundation for further progress to occur in the future.Dmitri Mendeleev anticipated the existence of unexampled elements to be observed, therefore leaving gaps in the ascending order of elements. Mendeleev was the historied discoverer of isotopes and r be gasses. In summary, science is a blend of logic and predilection and Mendeleev demonstrated these attributes through developing the periodic table (Western Oregon University, 2012). Dmitri Mendeleevs creation of the periodic table was con sidered one of the greatest triumphs in chemistry history as it allowed for further exploration to begin. Why do you think the development of the periodic table required input from a range of different citizenry?As many ar aw be, the development of the periodic table required numerous scientists such as John Newlands and Julius Lothar Mieyer. If not for these men, Mendeleevs table would not be as accurate as it is today. As time progressed, technology advanced scientists discovered noble gasses and determined each elements atomic number. Many scientists contend a vital role in developing our modern day periodic table as each person had a different familiarity and thought of chemistry. To conclude, the periodic table was never one mans discovery, but the result of numerous scientists explorations and experimentations.Each played a vital divulge in challenging/confirming the theories of their predecessors, recognising different patterns and properties between different elements . How did improvements in technology influence the development of the periodic table? With the improvement in technology from the 1800s through to present day the development of the periodic table has undergone significant changes. Since the development of the table by Dmitri Mendeleev in 1869, scientists make utilised brand-new technologies to produce a more accurate representation of the chemical elements.Scientists such as William Ramsay, who discovered noble gasses, drastically changed the periodic table adding a unit new group. In 1913, Henry Mosely significantly affected the periodic table with his discovery of nuclear charge. Ultimately, the nigh technological change is attributed to Glen Seaborg in 1940. His work on the discovery of atomic number reconfigured the periodic table, awarding him the noble prize in chemistry in 1951. Without technological advancements such as nuclear reactors, range and the chemical bond certificates system (Alexander Crum Brow)). Seaborg po ssibly would not have been able to discover what he did.In summary, the advancement in technology has importantly altered Mendeleevs original periodic table and will most likely continue with new synthetic elements being added. Briefly describe information we now have about atoms that was not available to earlier scientists who were identifying patterns and trends within early versions of the periodic table. What trends could they see, compared to what we now know? In the 20th Century, scientists have a greater understanding of atoms and the patterns they follow compared to those who invented the early versions of the periodic table.It was noted in the early 1800s, that matter consisted of lumpy particles called atoms. Towards the end of the century, J. J Thompson discovered electrons and their negative charge. He hypothesised that atoms would therefore expect positive charged particles. In 1869, scientists began to recognised patterns in properties originating from a number of kno wn elements, eventually developing the classification methods. During the early versions of the periodic table, it was determined by Henry Mosely to arrange elements in order of their atomic number.This pattern followed the periodic table concept more accurately than the arrangement of atomic weight. Another notable trend originated from glen Seaborg in the 1940s. Seaborg artificially produced new heavy mass elements such as neptunium and plutonium. Thus creating a new block in the table called antinides. To conclude our knowledge of atoms, their structure and patterns they form in the periodic table originating from the 18th century has developed. Essay Part This essay will provide a clear insight into the element of chlorine.It will include detail on the history of chlorine, its structure, position on the periodic table and the ions formed. The element of centilitre was discovered quite early compared to many other elements. Carl Wilhelm Scheele start-off produced the element in 1774 in Sweden. Scheele came across this element after combining the mineral pyrolusite and hydrochloric acid together. He discovered that this new gas reacted with metals, dissolved slightly in water and bleached flowers and leaves. At first, Scheele believed that the gas produced was oxygen, however Sir Humphry Davy proved in 1810 that this gas was new.Sir Davy so went on to name the new substance centilitre after the Greek word (Chloros) meaning greenish yellow. Chlorines element structure is mistakable to other elements that are situated in the halogens group on the periodic table. This element comprises an atomic number of 17 and weight of 35. 5. Chlorine is known to be an extremely reactive gas therefore providing reasons as to why it directly combines with the majority of other elements except for the noble gasses. This element is arranged into three shells. The first two shells are filled with electrons.Meanwhile the third contains only seven electrons. Chlorine is a nat urally occurring element, arising in the Earths crust and seawater. Its abundance in the Earth is about 100-300 parts per million (Chemistry Explained, 2013). This element is considerably well known to be a dense gas, containing a niggardliness rating of 3. 21g per litre. Chlorine is quite a strong oxidizing agent. In other words, it is notorious for taking on electrons from other substances. Nevertheless, the element chlorines special(prenominal) element structure dictates as to why it is positioned within the halogens group.Chlorine has been specifically positioned within the periodic table situated in group 17 because it belongs to the halogens family. It is known to be the second lightest element in the halogens group. Chlorine is situated in this group because it contains similar chemical properties to other halogen family members. Some chemical and physical properties of these elements are that are very reactive, they contain seven valence electrons, they are poor conductors and they are brittle when solid.Chlorine has a melting point of -100. 98Cand a boiling point of -34. C. Chlorine is heavier than air and proved very effective as a chemical weapon in the trenches and fox holes dug in World War One. Chlorine has been specifically positioned towards the top end of the halogens as it holds a notably low atomic number compared to other elements that are alike a part of the same group. In summary, Mendeleev and Seaborg essentially position chlorine within the halogens group due to its similar characteristics. The elements included in the halogens group are fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and astatine (At).Fluorine and chlorine, both have seven valence electrons in their outer shell. That seven-electron trait applies to all of the halogens. They are all just one electron shy of having full shells. The halogens have the trait of combining with many different elements. They are very reactive. You will frequently find them bonding w ith metals and elements from Group One of the periodic table. Fluorine is the most reactive of the halogens and reactivity decreases as you move down the column. Therefore, Chlorine is the second most reactive. As the atomic number increases, the atoms get bigger.Their chemical properties change just a small amount when compared to the element right above them on the table. Chlorine forms a negative ion by reason of a greater amount of electrons than protons. This atom has 17 protons and electrons. Due to the last unfilled electron shell, this element transforms into a negative ion. In simpler terms, a negative ion contains one more electron than proton. In scientific language, a negative ion is otherwise known as an anion. Chlorine is converted into an ion once gaining an extra electron from a different element. This process is essential for creating an ionic bond.Chlorines ion is known to be extremely fat-soluble in water, thus giving reasons as to why it bonds with sodium, formi ng sodium chloride. The ionic bond that forms is measured in terms of valence, meaning how much an element wants to bond with another element. To summarise, chlorine and sodium are a direct example of an ionic bond that forms when two ions chemically attach together. The uses of chlorine in public life are vast and continue to be used world-wide specifically for maintaining a clean swimming pool environment and many uses as a cleaning agent.