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Democritus created the first atomic model which was a sphere with no neutrons, electrons, or protrons. It helped people understand the concept of an atom and encouraged other scientists to further look into the science of an atom.
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He came up with the law of conservation of masses. It states that when two chemical substances' weights combine, it is equal to the weight of the newly formed compound.
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His theory was that all matter was made of atoms and that atoms are indivisible and industructable. He also said that all atoms are identical in mass and properties. Lastly he came up with that compounds are formed by a combination of two or more different kinds of atoms and that a chemical reaction is an arrangement of atoms.
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He discovereed the law of definite proportions. This law states that a compound regardless of how it was created, is composed of exact proportions of elements.
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It explains how atoms combine to form molecules. It is discovered by John Dalton.
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Faraday discovered that the reason why atoms were in compounds was because of electrical forces. The electrical forces were electrodes.
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It's a model that shows that electrons move around the nucleus in a cloud of energy.
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He discovered that electrons travel in seperate orbits around the nucleus. He also found out that the propety element is determined by the amount of electrons in the outer orbit.
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He discovered radioactivity which is the particles emitted from the nuclei.
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They discovered two important elements, radium and polonium.
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Planck proposed the quantrom theory which was to explain the color of glowing matters. He stated that energy is emitted every minute and discrete quantized amount of packets, rather than in an unbroken wave.
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The cathode rays led to his discovery of the negative charged electrons.
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He discovered a radioactive isotope of thorium called radioacinium. He also discovered nuclear fission which was the primary chemical process in nuclear reaction.
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Proposed the idea that light exists as little particles called protons. He also came up with a new way of counting and determining the size of atoms in a given space.
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This model states that the nucleus is positive and that there are negatively charged electrons outside the nucleus.
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Discovered by J.J Thomson, the model showed that atoms have negative charged electrons in a postive charged substrate.
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His oil drop experiment allowed him to find the unit charge of an electon. Then he found the calculation mass of the electon.
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Proposed the nucleus and that all electrons were in the occupied space around it.
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Shows that electrons are found in regions called orbitals around the nucleus.
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He discovered the wave nature of electrons. He proposed that particles can behave like waves.
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Discovered the quantram mechanical model which predicts the location of the electron. This is also known as the necleus surrounded by an electron cloud. The propability of fiding an election greatest is where the cloud is most dense.
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He discovered the neutron. The neutron is a particle that has no charge and it is a part of the nucleus.
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Her invention was to emmit neutrons to make them clash into the atom. This is what led to the discovery of the fission.
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He helped discover plutonium and all transuranium elements through element 102. He also identified more than 100 isotopes of elements on the Periodic Table.
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He did not belive in atoms. He thought matter was made of four elements, earth, fire, water, and air.
