CHEMISTRY (4.3 the subatomic particles and structure of atom)

cathode

The negatively charged plate is called ____

anode

The positively charged plate is ____

cathode-ray tube

The use of this device led to the discovery of the electron

joseph john thomson

He used the cathode-ray tube and electromagnetic theory that led to the discovery of the negatively charged particle

oil-drop experiment

Was used to quantify the charge of the electron

robert millikan

Used the oil-drop experiment

electrons

Negatively charged particle

plum pudding model

J.J Thomson proposed that an atom could be thought of as a uniform, positive, sphere of matter in whhich electrons are embedded

ernest rutherford

He decided to use the gold foil experiment

gold foil experiment

Used very thin foils of gold and other metals as a target of alpha particles that led to the discovery of proton and nucleus

nucleus

A positively charged dense core

protons

The positively charged particles in the nucleus

neutron

Electrically neutral particles

james chadwick

He used the alpha particle and beryllium experiment that led to the discovery of neutron

alpha particle and beryllium experiment

A thin sheet of beryllium was bombarded with alpha particles

neils bohr

He discovered the planetary model of an atom

planetary model of an atom

Speculated that electrons move in orbits around the nucleus

erwin schrodinger

He proposed the electron cloud model

electron cloud model

Speculated that electrons do not move in a set of paths around the nucleus but in waves