Final answer:
Removing protons from a lead atom results in a nuclear reaction, changing the atom's identity. This process is related to the foundational experiments of Ernest Rutherford, who demonstrated the existence of a dense, positively charged nucleus within atoms via alpha particle scattering.
Step-by-step explanation:
When protons are ripped out of a lead atom, a nuclear reaction has occurred, altering the identity of the atom. Ernest Rutherford's experiments with alpha particles and gold foil revealed the nuclear structure of atoms, showing that the positively charged protons are located in a dense nucleus.
This was a pivotal discovery in understanding atomic structure. The later experiments you mentioned, such as bombarding beryllium with alpha particles and observing the effects of beta decay in thorium-234, provided further insights into nuclear reactions and the interaction of particles with matter. These experiments form the basis for our understanding of nuclear physics and chemistry.