Transcript Project 1
OLYMPIADS + BRUTAL BRUCE Group 6 THE PROTON In 1812 Eugene Goldstein noticed during an experiment there were hydrogen nuclei. Those were also known as protons, or even the hydrogen in when separated from it’s electron. The proton has a positive charge. http://en.wikipedia.org/wiki/Proton PROTONS What are their properties? A proton is a subatomic particle with an electric charge of one positive fundamental unit Protons are much larger and heavier than electrons It is about 1836 times the mass of an electron Protons are found in the nucleus of atoms quark structure of the proton The number of protons in the nucleus determines the chemical properties of the atom Protons are observed to be stable and their theoretical minimum half-life is 1×1036 year THE NEUTRON The Neutron is the neutral part of the atom Discovered by Walther Bothe, Irène Joliot-Curie, Frédéric Joliot, and James Chadwick in the early 1930’s The neutron has to do with the strong force which holds the atom together (gravity is too weak at this level to hold the nucleus together), but when an atom is too large the atoms fall apart (this releases radiation). http://en.wikipedia.org/wiki/Neutron NEUTRONS What are their properties? Neutrons are subatomic particles with no net electric charge They are also found in the nucleus of an atom Quark structure of the neutron The number of neutrons determines the isotope of an element Neutrons consist of two down quarks and one up quark THE ELECTRON An electron is the negatively charged part of the atom Discovered by J. J. Thomson in 1897 Discovered with the use of cathode ray tube Used in many applications such as: radiation therapy, welding, electron microscopes, etc…. http://en.wikipedia.org/wiki/Electrons ELECTRONS What are their properties? An electron is a fundamental subatomic particle that carries a negative electric charge Electrons are found outside the nucleus of an atom Together with the atomic nuclei (protons and neutrons), electrons make up atoms An electron’s mass is approximately 1 / 1836 of the proton Electron mean lifetime is >4.6x10^26 years Electrons can also act as waves Nuclear and Hyphen notation Hyphen Notation • Hyphen notation is the written name of the element plus its mass number. Examples • Hydrogen-1 • Helium-3 • Uranium - 235 Nuclear Notation • Uses the first letter of the element plus it’s mass number and atomic number Examples Mass number 3 atomic number 1 H Why does it matter? • Nuclear and hyphen notation allow us to express different forms of the same isotope • For example, there are more than one hydrogen so simply writing “hydrogen “ does not mean one specific isotope • So by using hyphen notation, we are able to express a single isotope of hydrogen by showing it’s mass number or using nuclear notation to show hydrogen’s mass number AND atomic number For more information • http://teachers.popejohn.org/Mrs_Olsen/Ch3 Atom/Ch.3-Atom%2005.ppt Elemental Identities! Q: What gives an element its identity? A: The atomic number (number of protons in the nucleus) provides a unique identity for elements because each element contains a different number of protons. Example: Atomic # is 6….. It must be Carbon!!!! END