In your own words, explain how j. j. thompson's theory of atoms in the development of the modern atomic theory

 In 1897, J.J. Thomson discovered the electron, by demonstrating that cathode rays were negatively charged  and that the particles in neon gas are positively charged. The accepted model of the atom in that time did not account for negatively or positively charged particles, so Thompson;s theory of atom helped in the development of the modern atomic theory because it introduced the positively and negatively particles in the atom.