Atomic Structure/ Nuclear Chemistry

Atomic philosophy that atoms are indivisible and indestructible

Atomic theory

All elements are composed of tiny indivisible particles called atoms

Discovered electron using cathode ray

Discovered electron mass

9.109×10-31kg

Discovered protons

Discovered nucleus by concluding the atom is mostly empty space and that mass + positive charge is concentrated in smaller region

Discovered neutron

Atoms with different number of neutrons

Longer wavelengths transfers to matter, and vibrates molecules ex microwaves

Shorter wavelengths, carries more energy ex. X-rays

Certain materials emit light when struck with radiant energy and stops when that energy is removed

Discovered X-Rays

Connected x-Rays and naturally occurring phosphorescence materials

Spontaneous emission of particles and energy from atomic nuclei

Uranium core contains polonium radium uranium (pitchblend)

Penetrating rays and particles emitted by radioactive source

Nuclear radiation begins with unstable isotopes called this

Temperature change
Pressure
Presence of catalyst

Conserve mass (small amount is converted to energy during decay)

Attractive forces that are between all nuclear particles that are close together (protons neutrons)

Conversion of an atom of one element to the atom of another element, can occur from bombardment of particles to nucleus

Elements with atomic number greater than 83

Elements above 92 atomic number that none occur in nature

Region where stable nuclei don’t decay or change with time

Ratio of protons to neutrons

Time required for one half of the nuclei in a radioisotope sample to decay to products

Nuclei of certain isotopes bombarded with neutrons splitting nucleus into smaller fragments

Nuclei combine to produce nucleus of greater mass, creates more energy than fission

Produces neutrons that react with more fissionable atoms , must be controlled

Slows down neutrons by capturing them for reactor fuel