The Physics Of Atomic Theory

Around 2,500 years ago, Democritus and his partner Leucippus were the first ones to develop the atomic theory in written history. Their theory proposed that every kind of matter was made up of tiny particles, which were named atomos, which means that it is indivisible. This meant that Democritus and Leucippus thought there were little particles of everything, but, the next breakthrough in atomic theory wasn’t made until the early 1800s with a french chemist by the name of Antoine Lavoisier, he was the one who came up with the idea of the law of the conservation of mass, which states that matter stays the same even when it changes shape or form. Then, James Dalton said that all matter was made up of atoms, which were indivisible, and unbreakable.

He stated that this was a mysterious force but never continued his research on it. Then in 460 B.C. there was a philosopher named Democritus. Democritus and his mentor Leocippus posed the question that if he broke bread into multiple pieces how many would breaks would it take until there was no more bread. He then was able to make a few theories being all matter was created of atoms and atoms are solid but not invisible. However, there was a man named Aristotle and many other philosophers who disagreed with Democritus and said matter was composed of four main elements. Earth, fire, air, and water. For example, a liquid was made of water and a stone was made of rock. Therefore, Democritus’s theory “ was rejected by Aristotle, one of the most influential philosophers of Ancient Greece; and the atomic theory was ignored for nearly 2,000 years.”(

Within the last hundred years, the atomic model gone through dramatic changes allowing to apply the knowledge of matter understanding at atomic level into different industries like medicine such as MRI and X-Ray. This knowledge allowed doctors to treat, diagnose and certainly save millions of people throughout the years, which could not have been done without research being done on the structure of the atom funded continuously for these scientists to find more application which benefit people and comprehend the world we live in on an atomic level.

At the beginning of the twentieth century a scientist called Albert Einstein had a special theory about atoms. His theory was that atoms had a lot of energy locked within them. After this theory was published scientists worked hard to prove that this theory was true. After thirty years of experiments they discovered that within the nucleus there is a lot of energy and splitting the atom would release it.

Over the course of the last 5000 years, mankind’s knowledge has been constantly advancing. Chemistry, a branch of science, has experienced a tremendous leap and expansions since ancient Greek civilization. One of the major breakthroughs in the advancement in Chemistry was the creation of the Atomic theory, which laid a foundation for the modern-day Chemistry and future of science. The Atomic theory introduced the idea of atoms, which are defined as the discrete units of matter. There are five key scientists that significantly contributed to the Atomic model over a span of thousands of years. They are: Democritus, John Dalton, J.J. Thompson, Ernest Rutherford, and Niels Bohr.

Honor means to hold with high respect or esteem. My view of honor is to give respect to those who deserve it. Dmitri Mendeleev, the creator of the first periodic table, is one of those who deserve the respect honor has to offer. Dmitri Mendeleev was born February 8, 1834. When he was young, his father went blind and couldn’t work.

One scientist that helped was Werner Heisenberg. Heisenberg worked very closely with Bohr, sort of like an assistant. They both worked on the mathematical foundations of quantum mechanics. Heisenberg developed the uncertainty principle, which set the limits to the position and speed determined of an atom. Another person that helped was Max Born. Max Born was sort of an ‘unsung hero’ to quantum mechanics, as he did an incredible amount of work on the mathematics part of it. He discovered that the Schrodinger wave equation would be used to predict where the particle would be. The Copenhagen view thought up by these many scientists would be later known as the standard that we use

Atomic energy re-invigorated technological and scientific purpose of the early 20th century. Augmenting knowledge through scientific inquiry motivated researchers and academics to collaborate in labs and conferences in developing an emerging field. As discoveries dotted the path to scientific self-indulgence, the purported results of the research which was often purely coincidental, was promoted as yielding untold benefits to society. Medicine would be radically transformed and the scarcity of energy to fuel engines of economic growth would be a thing of the past (De Groot, Steg & Poortinga, 2013). The marvels of the atomic age, it seemed, would become the Holy Grail that would breathe renewed life to human progress.

He discovered the electron and experimented by testing the electric discharge in a high vacuum cathode ray tube. (Nobel Lectures.1967)

As technology advances so do the experiments to discover more about the atom. By 1911, Rutherford disproved Thomson's plum pudding model with his gold foil experiments. He discovered that atoms are mostly empty space and deflections are caused between a repulsive force between the positively charged nucleus and the alpha particles. James Chadwick, a co worker of Rutherford, found that there was another subatomic particle located in the nucleus called the neutron. While Rutherford’s model of the atom showed the electrons orbiting the nucleus, Bohr’s model shows the electrons traveling around the nucleus, the distance of the electrons from the nucleus are determined by energy. Then in the late 1910’s, Robert Millikin calculated the mass of a single electron by performing the oil droplet

In 1808, John Dalton published his theory that all materials were made up of atoms and that atoms can bond together in different combinations. After experimenting with his theory and proving it was indeed true alchemist, chemist and scientist were all on the hunt to find new atoms and this started a scientific revolution. With the inventions of better technology and the scientific innovation scientists were able to find many different atoms. Afterward chemist worked harder to determine whether these substance were elements. These scientist soon identified many groups to elements. A Russian chemist, Dimitri Mendeleev organized and formed the periodic table based on all of the information he had collected. Although Mendeleev did not have all

In 1896, Henri Becquerel observed “some rays of unknown nature” (Madame Curie, p. 153) radiating off of uranium salts. Marie, fascinated by these rays, took to studying this interesting phenomenon herself. As a result of these studies, she discovered an entirely new field of science, and coined the term “Radioactivity.” She also discovered two new elements, polonium and radium. This lead to the discoveries of new elements by other scientists. The next year, 1899, André Debierne discovered actinium. In just a few more years, there became a global race to element discovery. “It was a fruitful pursuit, to which we owe mesothorium, radiothorium, ionium, protactinium, and radio-lead.” (Madame Curie, p.194) The discoveries of these new elements led to our knowledge of science to change in new and dramatic ways. A lot of

The Zr4+ ion is more stable because it outer shell (valance shell) is complete following the octet rule. When this occurs, the atom is less likely to react because it is most stable. Comparing it to the Zr atom, the Zr atom does not have a filled valence shell.

The Discovery of the Atom first came from the Greeks which made a theory “The idea that all matter is made up of tiny, indivisible particles, or atoms, is believed to have originated with the Greek philosopher Leucippus of Miletus and his student Democritus of Abdera in the 5th century B.C. (The word atom comes from the Greek word atomos, which means “indivisible.”)” (InfoPlease Atomic theory)

Ernest Rutherford firstly developing the modern science by found the theory of radioactivity from an experiment. Radioactivity is “the emission of energetic particles or waves from atoms”