The Atom and Nuclear Physics

Who believed the atom was a solid sphere? Democritus What 3 things did Democritus propose about the atom? – Matter can not be divided , cannot be cut(atomos) – Small hard particles, that are made of the same material but are different shapes and sizes – They are always moving Read more…

Chapter 21 Atomic Physics

What is blackbody radiation? electromagnetic waves reflected off a blackbody What is a blackbody? object that has absorbed almost all electromagnetic waves What is an example of a blackbody? black hole What is ultraviolet catastrophe? failed prediction of classical physics that the energy radiated by a blackbody at extremely short Read more…

Ch. 13: Atomic & Nuclear Physics

Introduction Light it wave-like. Photoelectric Effect Light shining on various metal surfaces cause electrons to be ejected from the surfaces. Birth of Quantum Theory Developed in 20th century by Mark Planck. Energy only occurs in small amounts called quanta. (Explains nuclear and radiaiton phenomena). E=hf-W Wave-Particle Duality The concept that Read more…

atomic structure and nuclear chemistry

democritus all matter is made out of tiny, indivisible particles (atomos). no experimentation, no explanation of chemical behavior. aristotle did not believe in atoms. All matter is continuous, composed of air, water, fire and earth. his;refs weren’t challenged until the age of experimentation in the 18th century. john dalton proposed Read more…

Chapter 9 – Atomic Physics

atom The smallest particle of an element that can enter into a chemical combination electrons negatively charged subatomic particles quantum a discrete amount of energy photoelectric effect The emission of electrons that occurs when certain metals are exposed to light photon A “particle” of electromagnetic energy dual nature of light Read more…

Physics Chapter 10 Atomic Physics

3 Phenomena Blackbody radiation , the photoelectric effect, and atomic spectra. p.265 Blackbody Radiation states that a perfectly “black” body one that would absorb all light and other EM radiation incident upon it would also be a perfect emitter of EM radiation. Blackbody was said to emit blackbody radiation (BBR). Read more…

Nuclear Physics

Absorber Material that prevent radioactive emission from passing through it. ? Activity Number of radioactive emissions/counts per second- also known as “rate of decay”. ? Alpha emission Release of alpha particle from, unstable nucleus (A 2+ helium ion or a helium nucleus. ? Alpha particle The nucleus of a helium Read more…

Nuclear Physics Vocabulary

Alpha decay the radioactive decay process in which the nucleus of an atom emits an alpha (helium) particle Beta decay occurs when a nucleus has too many neutrons for the protons present, a neutron converts to a proton, a negative electron is released, and an antineutrino is released Gamma radiation Read more…

Atomic/Nuclear Physics

John Dalton’s model All matter is made up of atoms. They are the smallest particles of matter and cannot be broken into smaller units. Joseph Thomson’s model (Cathode ray experiment) There are negative electrons. The overall charge of an atom is neutral. Plum pudding model – Negatively charged electrons are Read more…

IB Atomic Physics

Nuclide Specific atomic structure (protons + neutrons) Nucleon A Nuclear Particle (protons or neutrons) Isotope Two atoms of the same element with a different atomic mass Nuclear Transmutation Nuclear Reaction in which one nuclide is changed into another nuclide (Fusion or Fission) Photon Particle of light Ionization The process of Read more…

Physics – atomic structure

What determines the atomic number? The number of protons What determines the mass number? No. neutrons + no. protons Define the term ion An atom with either more or less electrons than protons Define the term isotopes Different forms of an element with the same number of protons but a Read more…