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R. J. John Dalton's Theory Of Atoms

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The Atomic Theory

The atom seems very simple and fundamental to most people but when you look into it further, it can get very complex and the history goes way back to 400 BCE. It all started when a man named John Dalton came up with the first atomic theory. Daltons theory consisted of 5 parts. He believed that all matter is composed of extremely small particles called atoms which cannot be subdivided, created, or destroyed, atoms of a given element are identical in their physical and chemical properties, atoms of different elements differ in their physical and chemical properties, atoms of different elements combine in simple, whole number ratios to form compounds, and in chemical reactions, atoms are combined, separated, or rearranged …show more content…

J.J. Thomson was one scientist who did this. He used a cathode ray to discover the existence of electrons in an atom. With this experiment, he was also able to conclude that electrons are negatively charged because the cathode ray came from a negative charge. Another scientist named Ernest Rutherford discovered the nucleus. He made a model of an atom that he called the plum-pudding model because that is what it resembled. Rutherford also did an experiment that was called the gold foil experiment. This proved that the nucleus of an atom has positive particles in it. He found this out because he directed a thin line of particles at the gold foil and some particles bounced off and were reflected. This also helped him hypothesize that the area outside of the nucleus is not just empty space, it is the electron cloud. Another thing that he was able to hypothesize was that the nucleus nearly makes up all of the mass of an atom. Rutherford was a very influential person to the discoveries of the atom. His gold foil experiment also led to finding protons. Protons are positively charged particles in the nucleus. The other particles that make up the nucleus are neutrons. Neutrons …show more content…

The quantum numbers are basically different orbitals that electrons can be found on. The different orbitals are s,p,d, and f. Each level can only hold a certain amount of of electrons until they move on to the next. The s orbital can hold 2 e-, the p orbital can hold 6 e-, the d orbital can hold 10 e-, and the f orbital can hold 14 e-. A way to find the quantum number of an element is to use the diagonal rule. Each element has different quantum

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