Evolution of Modern Atomic Theory: A Timeline

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Atomic Theory Historical SHE Task
1. Construct a timeline which shows the development of the modern atomic theory. Include a minimum of 5 and a maximum of 15 significant events in your timeline.
442 BC thinking about matter

Democritus, a Greek philosopher, co-originated the thought (with his teacher, Leucippus) that all matter is composed of indivisible elements.
1803 John Dalton and atoms

John Dalton, a British chemist and physicist, developed a theory that matter is simply composed of atoms of different weights and is combined in ratios by weight. Also proposed that these atoms are spherical, and are in motion.
1870 Cathode ray tube and TV (1870's)

Sir William Crookes constructed a primitive cathode ray tube, which later became the basis for television.
1896 X-rays developed

Wilhelm Rontgen discovered that certain chemicals …show more content…

In fission, an atom is split into two or more smaller, lighter atoms. Fusion, in contrast, occurs when two or smaller atoms fuse together, creating a larger, heavier atom. Fission is the splitting of a large atom into two or more smaller ones. Fusion is the fusing of two or more lighter atoms into a larger one.
5. Discuss the possible benefits and concerns of nuclear energy as a power supply.
Nuclear power is considered a prominent alternative, despite the disregard it was met with in the 1970s. This is because it’s now being touted as a more environmentally beneficial solution since it emits far fewer greenhouse gases during electricity generation than coal or other traditional power plants. Nuclear energy is cost-competitive. Generating electricity in nuclear reactors is cheaper than electricity generating from oil, gas and coal, not to speak of the renewable energy sources.
6. Discuss the use of radioactive isotopes in an application of nuclear

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