Science

Atom definition

The smallest particle of an element that still has the properties of that element

Nucleus definition

Dense center made of protons and neutrons positively charged where the mass of the atom is located

Electron cloud

space surrounding the nucleus broken down into regions of space called “Shells”

What is an electron

Carries the negative charge

What is a proton

carries positive charge

What is a Neutron

has a neutral charge, found inside the nucleus

Who is Democritus?

first to name the atom; Atomas= “indivisible” in Greek

Thought that there was nothing smaller than an atom

Who is John Dalton?

Proposed the solid sphere model

first scientific model of an atom

stated a solid sphere cant get any smaller

Who is J.J Thompson

Proposed the plum pudding model

added electrons

Cathode Ray tube experiment

Who is earnest Rutherford

introduced the nuclear model

Nucleus added in the middle of atom

Gold foil experiment

Who is Niels Bohr

Electrons go to different energy levels

proposed the planetary model

Who is Erwin schodinger and Werner HeisenBerg

Quantum model; most advanced

Isotope definition

Same element different mass numbers

Atomic number:

tells the number of protons

Mass number:

tells the number of protons and neutrons