STRUCTURE OF ATOMS(PART 1)

Michael Faraday

• related electricity to atoms by “if we adopt atomic theory then the atoms of bodies which are equivalent to each other in their ordinary atomic theory”

1890’s

• scientist focused on transmission of energy to space through waves

Cathode-ray tube

• evacuated glass with 2 electrodes attached to its opposite ends

• used as old models of television sets

Joseph John Thompson(1897)

• used the CRT to investigate composition of cathode ray

• discovered negatively charge

• mass to charge ratio of electrons

• plum-pudding model

Plum-pudding model

• electrons are evenly distributed like raisins on the surface of pudding

Corpuscles

• particles determined by mass to change ratio

• later called as electrons

• april 29, 1897

Ernest Rutherford

• said that atom might not be solely composed of negatively charge particles

• atom is a vast empty space

• atomic structure is similar to miniature solar system

Robert Millikan

• Oil Drop experiment

• charge of electron

• mass of an electron

• Nobel prize in physics in 1923

Wilhelm Roentgen

• german physicist

• noticed that CRT may cause glass to emit unusual rays that darkens photographic plates

Antoine Becquerel

• fluorescent properties of substance

• uranium ores

Marie Curie

• coined “Radioactivity”

• noble prize in physics

Pierre Curie

• noble prize in chemistry

• polonium and radium

Types of radiation:

alpha

• least penetrating power

Gamma Ray

• most penetrating capability

Ernest Rutherford, Ernest marsden, and hand Geiger

• worked in laboratory of j.j thompson

• studied alpha and beta ray

• Gold foil experiment

James Chadwick

• student of Ernest Rutherford

• neutrons

• these particles to smash nucleus

Niels Bohr

• electrons revolve around the nucleus with specific distance

• electrons with low energy= nearest to nucleus

• electrons with high energy= farther to nucleus

Heisenberg uncertainty principle

• electrons are not confirmed to moving along predefined orbits

Erwin Schrodinger

• electrons are located with the same location

Orbital

• space around atom where electrons can be found 95%