Structure of At...

When an electric discharge is passed through gaseous hydrogen, the H₂ molecules dissociate and the energetically excited hydrogen atoms produced emit electromagnetic radiation of discrete frequencies. The hydrogen spectrum consists of

Absorption spectrum, seen as dark lines in an otherwise continuous spectrum, for a given material results from the material's (atom or molecules)

Emission spectrum of a material results from the material's (atom or molecules)

Photoelectric effect established that light

Isotopes are the atoms with

Isobars are the atoms with

Correct expression for mass number A is

Rutherford’s α–particle scattering experiment supported the discovery of

Charge on the electron was determined by

Cathode rays or cathode ray particles are