The scientist who is credited with discovery of 'nucleus' in an atom is
Rutherford
Niels Bohr
Balmer
J J Thomson
A.
Rutherford
Rutherford was credited with the discovery of nucleus at the centre of atom based on his α-scattenng experiment observations.
In a sample of radioactive material, what percentage of the initial number of active nuclei will decay during one mean life ?
63 %
69.3 %
37 %
50 %