More handpicked essays just for you.
Historical development of atomic structure (rutherford and bohr model of the atom
Short paragraph on the discovery of electrons
Short paragraph on the discovery of electrons
Don’t take our word for it - see why 10 million students trust us with their essay needs.
Many people think Thomson discovered the electron but actually, what he discovered was that cathode rays were streams of negatively charged particles with a mass about 1,000 times smaller than a hydrogen atom. He claimed that these particles, which he called “corpuscles,” were the things that atoms were made from. The term “electron” predated Thomson's discovery—a few years earlier Irish physicist G. J. Stoney had proposed that electricity was made of negative particles called “electrons,” and scientists had adopted the word to refer to anything with an electric charge. However, Thomson, who was a physicist at Cambridge University, was the first to suggest that these particles were a building block of the atom.
Thomson proposed (1904) a model
In 1895, Professor Wilhelm C. Roentgen, a German physicist, was working with a cathode ray tube, much like our fluorescent light bulb. The tube consisted of positive and negative electrodes encapsulated in a glass envelope. On November 8, 1895, Roentgen was conducting experiments in his lab on the effects of cathode rays. He evacuated all the air from the tube and passed a high electric voltage through it after filling it with a special gas. When he did this, the tube began to give off a fluorescent glow. Roentgen then shielded the tube with heavy black paper and discovered a green colored fluorescent light could be seen coming from a screen located a few feet away from the tube.
Physicist in the 1900 first started to consider the structure of atoms. The recent discovery of J. J. Thomson of the negatively charged electron implied that a neutral atom must also contain an opposite positive charge. In 1903 Thomson had suggested that the atom was a sphere of uniform positive electrification , with electrons scattered across it like plum in an pudding. (Later known as the Plum Pudding Model)
The cathode ray tube was invented in 1875 by the name of Sir Williams Crooke. Yet he wasn’t the one to make the big discovery. In 1897, a man by the name of J.J. Thompson conducted a series of experiments to prove the existence of subatomic particles. He wasn’t 100% correct with all of his claims he made but broke the theory John Dalton stated that the smallest form matter could be broken down to was an atom. Having shown the world that there was smaller than an atom, it later caused others to question and dive even deeper.
During the cold winter of 1895, a German scientist by the name of Wilhelm Conrad Roentgen was working with a cathode-ray tube when he noticed nearby crystals were glowing. When Roentgen reached for the crystals he was amazed when the shadow cast on the crystal was not of his whole hand, but just his bones. Roentgen covered the tube with heavy black paper and saw that the crystals still glowed and the shadow of his hand bones still shown through, he then determined that a new ray was being emitted that could penetrate through thick materials. (1.) He later found that the rays could pass through most anything, but would cast a shadow of solid objects; these shadows could then be captured on film. Among the solid objects Roentgen shot with these rays was human tissue, the rays would penetrate the tissue, but the bones would cast a shadow, which could then be caught on film. One of Roentgen’s first experiments with X-rays was on his wife’s hand where, on the film, you could see her hand bones and her wedding ring. (1.) While the discovery of x-rays was a huge advancement in medical technology, they were not used in the medical field at first. Instead the mystical invisible rays that could penetrate solid objects were used in the industrial field.
physics. The work of Ernest Rutherford, H. G. J. Moseley, and Niels Bohr on atomic
The Earth is not a piece of quartz - it’s like a stone with many imperfections and scratches, and though it retains its scratches, it attempts to heal them; it bandages its wounds. To heal a wound, though, it must be first isolated: and in the case of the world, it is literal flaw that resides with the mask of a wound - combated, though not incapacitated, by the innovators of the Earth. A telephone, refrigerator, microwave, civil rights and gender equality - not only technology, but even a concept as imperative as liberation or equality have altered the globe (as humans see it), for the better: technology has made life easier for humans, ideal rights and equality have been gifted to those that require it, and efforts have been exclaimed in order to protect the natural amenities that are taken for granted. The reason adhered to by the innovators, dedicated to creating the aforesaid circumstances, is rather simple: they endeavor as they do because of the profit that befits not only themselves, but the world in doing so. When Alexander Graham Bell and Antonio Meucci developed the telephone, they distributed communication among the masses (a profit), and thereby changed the globe for the better; that same reason is reflected throughout the ages: Percy Spencer, inventor of the microwave, gained favorable avail via his invention for not only himself, but the Earth as well. Thus, the innovators of the world retain that reason: they change things for the better because of the positive benefit that would befit doing so - the positive benefit for not only themselves, but the world. Nikola Tesla, one of those innovators, arguably fathomed that reason more than anyone. “Born on July 9, 1856, in Smijan, Croatia, Tesla was the child of a clergy...
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.
The Atomic Theory began in roughly 400BC with Democritus in Ancient Greece and is universally believed to be correct today. Democritus who was born in 460 BC and died 370 BC and is known as the father of modern science. Democritus proclaimed that everything is made up of atoms. He continued his theory to say that atoms will always be in motion, between atoms there is empty space, atoms are unbreakable, there are an infinite number of atoms all different sizes and shapes. He also said that iron atoms are solid and strong and have hooks to lock them together, water atoms are smooth and slippery, salt atoms have sharp jagged edges because of its taste and air atoms are light and spiralling.
In the beginning of the 1800s John Dalton, an English scientist did work some work on gases, which lead him to the creation of a complex system of symbols for all known elements at the time. He took all the information he had collected, along with the Laws of Conservation of Mass, Definite Composition and Multiple Proportions and updated Aristotle's theory of matter with the Atomic Theory of Matter, which stated: - All matter is composed of tiny, indivisible particles called atoms. - Atoms of an element have identical properties. - Atoms of different elements have different properties. - Atoms of two or more elements can combine in constant ratios to form new substances. In the late 1800s a man named J. J. Thomson did some experiments, who's results did not agree with Dalton's Atomic Theory. Thomson passed electricity though gases, my his experiments, he theorized the existence negatively charged subatomic particles he called electrons. From this theory Thomson created a model of a atom which had the electrons placed evenly inside the atoms. In the early 1900s a Japanese scientist named H. Nagaoka designed an atom model as a large sphere surrounded by a ring of negatively charged electrons. Also, during the early 1900s (1898-1907) a physicist named Ernest Rutherford worked on experiments to test current atom models. His experiments involved shooting rays of alpha particles (small positively charged particles) though very thin pieces of gold foil. Based on Thomson's model, Rutherford hypothesized that the alpha particles would travel through the gold foil mostly unaffected by the gold. He was right. Most of the particles did pass through, but a small amount of particles were deflected. From this Rutherford hypothesized that the atoms must have a small positively charged core, the nucleus, which is surrounded by mainly empty space, which contains the electrons. In 1914 Rutherford made up the word "proton," which were subatomic particles that had a positive charge. A student of Rutherford's, a man named H. G. J. Moseley was the one who gathered the empirical support for Rutherford's work. In his experiments he used X-rays to show that the positive charge in the nucleus grows by one, from each element to the other. From this Moseley devised the concept of Atomic Number. In 1932, James Chadwick established that the nucleus must contain heavy neutral particles as well as positive ones, this was to explain the entire mass of the atom.
the bulk to ordinary matter; the volume of an atom is nearly all occupied by the
The next big step in the discovery of the atom was the scientific test that proved the existence of the atom. After the discovery of the atom we had the discovery of subatomic particles. With the discovery of the subatomic particles came the research, which came from experiments that were made to find out more about the subatomic particles. This research is how we uncovered that most of the weight of an atom is from its nucleus. With the gold foil experiment, tested by Ernest Rutherford, he discovered the existence of the positively charged nucleus. He proved this when the experiment was happening, a small fraction of the photons th...
Throughout Thomson’s life he made many contributions to science. These include discoveries in thermodynamics and the age of the Earth, as well as innovating the Transatlantic Cable and inventing a tide meter. After exploring thermodynamics for some time, he developed the second law of thermodynamics. This law states that there cannot be a reaction that is completely efficient; a portion of the energy is lost to heat in each reaction. It also says that heat flows to areas that...
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...
Humans these days take electricity for granted. We don’t truly understand what life was like without it. Most young adults will tell you their life does not depend on electricity, but they aren’t fooling anyone. They all know that their life depends on electricity; whether it’s television, their phone, Google, or the lights in their house. We need to stop taking those things for granted and give credit where credit is due. That is why I chose to write about the scientists who contributed to the discovery of electricity, which then helped modern scientists fuel the electricity phenomenons we now have today.
The understanding that matter was composed of atoms was changed with the discovery of smaller particles than the atoms, which are protons, neutrons, and electrons. But during the 1960’s, the multitude of particles being discovered was making the understanding that matter is composed of protons, neutrons, and electrons, insufficient. Murray Ge...