Andee Fonseca

Democritus, Leucippus, Dalton, Bohr, JJ Thomson, and Rutherford are a few of the many intelligent scientists that contributed to the development of the atom.

Why were they vital to the development of the atom?

Democritus knew that if you took a stone and cut it in half, each half had the same properties as the original stone. He reasoned that if you continued to cut the stone into smaller and smaller pieces, at some point you would reach a piece so tiny that it could no longer be divided. Democritus called these infinitesimally small pieces of matter atomos, meaning "indivisible." He suggested that atomos were eternal and could not be destroyed. Democritus theorized that atomos were specific to the material that they made up. It is said that another scientist, Leucippus, helped him develop this theory; though, there is speculation on whether that statement is true or not.

Through his observations of morning fog and other weather patterns, Dalton realized that water could exist as a gas that mixed with air and occupied the same space as air. Solids could not occupy the same space as each other; for example, ice could not mix with air. So what could allow water to sometimes behave as a solid and sometimes as a gas? Dalton realized that all matter must be composed of tiny particles.

In 1913, Bohr published a theory about the structure of the atom based on an earlier theory of Rutherford's. Rutherford had shown that the atom consisted of a positively charged nucleus, with negatively charged electrons in orbit around it. Bohr expanded upon this theory by proposing that electrons travel only in certain successively larger orbits. He suggested that the outer orbits could hold more electrons than the inner ones, and that these outer orbits determine the atom's chemical properties.

Thomson discovered that cathode rays were streams of negatively charged particles with a mass about 1,000 times smaller than a hydrogen atom. Thomson was the first to suggest that electrons were a building block of the atom and Ernest Rutherford discovered the atomic nucleus.

These men were determined scientists that set out to understand the world better. While one maybe improved on a previous scientists theory, another one may have created his own theory. Also, the scientists different ways of thinking helped them come up with different theories concerning the atom. As a whole, these theories are combined to explain what we know of the atom present day. The earlier scientists figured out the atom logically instead of through physically through experimentation like the later scientists.

Democritus and Leucippus had to have great understanding and insight on the way the world works to be able to come up with such complex theories with no way to be sure that they were right and no proof to prove their thoughts. Technology and the advantage of having previous theories to help them definitely put later scientists at an advantage over the earlier ones. They still had to work hard to find out information about the atoms, but they were able to utilize technology and build on a previous foundation, whereas the previous scientists basically had to start out from scratch by just pondering the ways of the world. It's incredible that they were able to come up with such complex theories just by thinking deeply about something.

The atomic theory is still a theory not only because it has a few mistakes and it is not completely proven, but also because it is not complete and their are things still being discovered about the atom.

It is important that we understand the structure of the atom because everything is made out of atoms; also, by understanding the structure of it, we may be able to better understand it's capabilities, such as the fact that splitting an atom causing a mass explosion. There still may be more that an atom can do that we haven't discovered yet.

www.visionlearning.com
www.lucidcafe.com
www.infoplease.com