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John Dalton- The modern atomic theory
This was the date when his theory was first published he did not have an experiment John Dalton used his own theories and laws to find his answers. The conclusion of the theory is that Atoms cannot be created and or divided into smaller paricles and they can't be destroyed in a chemical reaction and or rearranged in one as well. Dalton's contribution was the atomic theory -
Michael Faraday- Electro magnetic induction
Michael discovered electro-magnetic induction and studied how electricity affected things. In his experiment he split molecules using electricity and developed the laws of electrolysis. He did so many experiments he coined the term Electrolysis.
Conclusion splitting molecules by electricity led to the law of Electrolysis
Contribution- electro magnetic induction -
J.J Thompson- Charge/ mass of electron
he demonstrated that atoms are actually composed of aggregates of charged particles. He did this by using Cathode rays which was when the two charged were together a current would be formed which is cathode rays this was to show the charge/ mass of electron. Of course he was the founder of electrons. the very large e/m of the electron is due to an ordinary charge and a very small mass, much smaller than that of the lightest atom. Contributions atom containing positve and negative particles. -
J.J Thompson- leptons
JJ thompson discovered the lepton and it is basically the same thing as the quark it is a is an elementary particle and a fundamental constituent of matter. it makes up protons and neutrons.
Conclusion- discovered the lepton and the relations it has with the necleus.
Contribution- Leptons -
Albert Einstein- E= Mc2
he made the famous equation e=mc2 he used his equations to discover the movement of the body e=energy m= mass and c2= a very large number the square of the speed of light.
Conclusions- e=mc2
Contributions- theory of relativity -
Ernest Rutherford- Postively charged nucleus
In his experiment alpha particles consisting of postively charged helium atoms were fired into a thin sheet of golden foil.
Conclusion he was wrong negative particles traveled around the nucleus which is postively charged.
Contributions- the negatively charged electrons hover around the postively charged nucleus -
Neils Bohr- Energy levels
Neils explained that electrons travel around the nucleus in exact paths. These paths are always at a certain level away from the nucleus. He also stated that electrons cannot travel in between each path, but they can hop from one path to another.
Conclusion- electrons travel in paths around the nucleus
Contribution- electron paths -
Ernest Rutherford- proton/charge
Rutherford discovered the proton while undergoing an nitrogen gas experiment that involved some alpha particles showed that the nitrogen atom broke down under great force from collision and the particle found was part of its nucleus.
Conclusion- used nitrogen gas and alpha particles to collide under great force and what was left was part of a particle from the nucleus of the nitrogen atom.
Contribution- discovered the proton -
Ernest Rutherford- Composition of electricity
Rutherford analyzied the( - +)electrons that flow around the electrical current he used this to analyze its flow through the connector until an electiral charge was present.
Conclusion- analyzed how the composition works and realizing that electrons orbit around the nucleus not in the same orbit.
Contribution- the Composition of Electricity -
de Broglie- particles and waves
Discovered that electrons had a dual nature-similar to both particles and waves. Particle/wave duality.
Conclusion Since the energy E of a photon equals Planck's constant times the frequency f, or E=hf, de Broglie reasoned that the momentum p of an electron would equal Planck's constant divided by the wavelength l, or p=h/l.
Contribution- electrons had a dual nature-similar to both particles and waves. -
James Chadwick- Neutral Neutron
Experiment used radiation on the particles which led him to the discovery of the neutron he called it that when it had no electrical charge
Conclusion- since the particles had no electrical charge after the experiment he called them neutral
Contribution- no all particles had charge to them which led to the neutron -
Murray Gell Mann- Quarks
He discovered a new atomic particle called quarks which is a building block of matter and is a elementary particle and fundamental constituent. there are 6 types of quarks which are known as flavors. Up, down, charm, strange, top, bottom
Conclusion- discoverd the existence of a new level of atomic particles called Quarks.
Contributions- Quarks a new level of matter
