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Physical science periodic table
Contribution of dalton to scientific knowledge
Scientist contribution to the atomic theory
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Recommended: Physical science periodic table
Development of the Periodic Table
Introduction:
The Periodic Table of Elements is a table that arranges all known chemical elements by order of their atomic numbers. During the 1600s, vast amounts of knowledge about the properties of elements and their compounds were discovered and by 1869 63 elements had been discovered. As more and more elements were discovered, scientists began to recognise similarities between their properties and began to devise means of classification. Thus the periodic table of elements was created. The current periodic table contains 117 elements, however more may yet be discovered. The elements in the periodic table are classified in groups, periods and blocks. Groups refer to elements with similar properties and are the vertical columns of the table. The periods are the horizontal rows and illustrate the number of valence electrons each element has (how many electrons are in the outer shell of the element). The position an element is in on the table allows a scientist to easily judge its properties, its reactivity and its similarities to other elements.
Dmitri Mendeleev’s Periodic Table:
Dmitri Mendeleev, a Russian scientist, is said to be the father of the periodic table. In 1947 Mendeleev, while working on a textbook, began to organise the 63 elements that were known at the time in groups that displayed similar properties. Mendeleev found it difficult to classify certain alkali metals and metals, and while trying to find a way to classify them he began to notice that the properties and atomic weights of halogens and alkali metals shared similar patterns. He then began to investigate extensions of these patterns within the other elements. Mendeleev created a card for each of the known elements that sh...
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...the first version of the atomic theory, which then later allowed John Dalton to expand on the atomic theory to create a method of discerning atomic weight, was crucial in the development in the table. It was through finding the atomic weight of elements as well as classifying their properties that allowed Mendeleev to create his periodic table and discern possible new elements.
The work of JJ Thompson and James Chadwick was also important in creating the ‘finalised’ version of the periodic table. The discovery of the electron and then later the proton and neutron not only allowed for scientists to start trying to create a detailed model of the atom but also allowed for Henry Moseley to notice the patterns of protons between elements and thus create a more accurate rendition of Mendeleev’s table by ordering the elements by atomic number rather than atomic weight.
Primo Levi’s personal relationship to his profession as a chemist shows that philosophically and psychologically, he is deeply invested in it. His book THe PeriOdic TaBLe shows that his methodology cannot be classified as either purely objective or purely subjective. He fits into the definition of dynamic objectivity given by Evelyn Fox Keller in her book Reflections on Gender and Science.
When designing my periodic table, I probably looked up a million websites. I used Wikipedia, horses.animal-world.com, and horses.petbreeds.com. I used the petbreeds website for my information, the animal-world website for deciding the categories, and Wikipedia for deciding which horse breeds go in which category. But those were just for my final draft. Before that, I organized in about 3-5 different ways, trying to find the most efficient way of having the most elements and have then going from left to
Just as the title of the chapter suggests, the main focus of Chapter 11 is how elements found on the Periodic Table are not always what they appear. Kean begins this chapter with describing how elements can be unpredictable in some conditions, and uses example from the past to...
This showed that dissolved gases were mechanically mixed with the water and weren?t mixed naturally. But in 1803 it was found that this depended on the weight of the individual particles of the gas or atoms. By assuming the particles were the same size, Dalton was able to develop the idea of atomic weights. In 1803 this theory was finalised and stated that (1) all matter is made up of the smallest possible particles termed atoms, (2) atoms of a given element have unique characteristics and weight, and (3) three types of atoms exist: simple (elements), compound (simple molecules), and complex (complex molecules).
Although the atomic theory was developed in increments, George Johnston Stoney is most famous for contributing the term electron: fundamental unit quantity of electricity. Stoney would develop the concept fourteen years before he coined the term electron. He also made contributions to the theory of gasses, cosmic physics, and estimated the number of molecules in a cubic millimeter of gas.
Dmitri M. enrolled in the division of mathematical and natural sciences of the Main Pedagogical Institute of St. Petersburg, Ivan Pavlovich’s alma mater. There he worked with Aleksandr A. Voskresenkii, also known as the “Grandfather of Russian Chemistry”. In St. Petersburg, he wrote his first scientific paper, “The Analysis of Finnish Allanite and Pyroxene”, this paper led to his curiosity of building the periodic table. He graduated in 1855, where he won a gold medal for being first in his class. After a few years, Mendeleev’s thesis On Specific Volumes and The Structure of Siliceous Combinations, resulted in him being able to teach theoretical and organic chemistry at the University of St. Petersburg.
The elements in the columns down the periodic table form groups. The major groups are numbered but often the numbers are given as Roman numerals (the first group, the blue column in the above diagram, is referred to as group I etc). Elements within the same group similar chemical properties but often show a systematic variation in extent or speed of reaction as the group is descended. For example all of the group one elements (the alkali metals) react vigorously with water to form water soluble alkalis with the subsequent production of hydrogen gas.
Over the years there have been many scientists studying the atom and making huge discoveries. Although all of them have been on the right path, Niels Bohr was credited with having the most correct atomic model and electron mechanics until recently. Coming from a very educated background, Bohr came up with his atomic theory which corrected Rutherford's atomic theory. His discovery made a huge impact on what everyone else thought about the atom and left a very complete and thorough explanation of the atom.
Dmitri Mendeleev was one of the most famous modern-day scientists of all time who contributed greatly to the world’s fields of science, technology, and politics. He helped modernize the world and set it farther ahead into the future. Mendeleev also made studying chemistry easier, by creating a table with the elements and the atomic weights of them put in order by their properties.
The modern periodic table is very much like a later table by Meyer, but arranged, by Mendeleev’s, but it had to be according to the size of the atomic weight. The only thing though that was made by Mendeleev’s was Group 0, which was then added by Ramsay.
The Periodic Table of Elements is commonly used today when studying elements. This table’s history begins in ancient times when Greek scientists first started discovering different elements. Over the years, many different forms of the periodic table have been made which set the basis for the modern table we use today. This table includes over 100 elements and are arranged by groups and periods. Groups being vertical columns and periods being horizontal columns. With all of the research conducted over the years and the organization of this table, it is easy to use when needed.
Later, other scientists found other triads and recognised that elements could be grouped into larger sets (more than three). However the poor accuracy of measurements for atomic weights made it difficult in grouping such elements.
John Dalton was a famous chemist born in Eaglesfield, Cumbria, United Kingdom. He lived from 1766-1844. He was important because he made a theory called Dalton’s atomic theory. Dalton’s atomic theory stimulated further research and promoted speculation about the structure of atoms.
Then, in 1766 was born a man named John Dalton born in England. He is known as
Scientists from earlier times helped influence the discoveries that lead to the development of atomic energy. In the late 1800’s, Dalton created the Atomic Theory which explains atoms, elements and compounds (Henderson 1). This was important to the study of and understanding of atoms to future scientists. The Atomic Theory was a list of scientific laws regarding atoms and their potential abilities. Roentagen, used Dalton’s findings and discovered x-rays which could pass through solid objects (Henderson 1). Although he did not discover radiation from the x-rays, he did help lay the foundations for electromagnetic waves. Shortly after Roentagen’s findings, J.J. Thompson discovered the electron which was responsible for defining the atom’s characteristics (Henderson 2). The electron helped scientists uncover why an atom responds to reactions the way it does and how it received its “personality”. Dalton’s, Roentagen’s and Thompson’s findings helped guide other scientists to discovering the uses of atomic energy and reactions. Such applications were discovered in the early 1900’s by using Einstein’s equation, which stated that if a chain reaction occurred, cheap, reliable energy could b...