In early atomic theory, who proposed that atoms of the same element are identical in mass and properties?

In the context of atomic theory, what did Robert Millikan determine about the electron from his oil-drop experiment?

In atomic theory, what was Henry Moseley’s key contribution to organizing the periodic table?

In early atomic theory, what did Democritus believe an atom was?

Atomic Theory: Who is most commonly credited with arranging the periodic table by increasing atomic mass and using repeating chemical properties to group elements?

The plum pudding model of the atom states that:

Which statement best describes the current (quantum mechanical) model of the atom?

In atomic theory, the electron cloud model describes electrons as existing in regions of probability rather than fixed orbits. Who is most closely associated with developing this electron cloud (quantum mechanical) model?

In atomic theory, the electron cloud (quantum mechanical) model describes electrons as existing in probability distributions rather than fixed orbits. Who is most closely associated with developing this model?