Leaving Cert Chemistry - Scientists

John Dalton

Daltons Atomic Theory

William Crookes

Cathode Rays (Maltese Cross / Paddle Wheel)

JJ Thompson

Electron (negatively charged)

Ratio of charge to mass of the electron (e/m)

George Stoney

Named the electron

Robert Milikan

Oil Drop Experiment

Discovered the size of the charge on the electron

Found the mass of the electron using e/m

Ernest Rutherford

Gold Foil Experiment

Proton - positive charge in nucleus

James Chadwick

Neutron

Bombarded Beryllium with alpha particles

Niels Bohr

Electrons revolve around the nucleus in fixed paths called orbits at a precise distance from the nucleus

Bohr's Theory

Louis de Broglie

Electrons have a wave nature

Erwin Schrödinger

Shapes of the atomic orbitals

Robert Boyle

First accurate definition of an element

Humphrey Davy

Discovered elements by passing electricity through their compounds

Henry Moseley

Used X-Rays to discover the number of protons in an atom (atomic number)

Johann Dobereiner

Law of Triads

John Newlands

Law of Octaves

Dmitri Mendeleev

Periodic Table

Brought an order to the list of elements