Water , H2O, is a molecule made of oxygen and hydrogen. The bonds that hold water molecules together are due to shared ELECTRONS, and known as covalent bonds
The periodic table of the elements is a tabular display of the chemical elements, which are arranged by atomic number, electron configuration, and recurring chemical properties.
The original radioisotope underwent double-alpha decay, where the original nucleus lost a total of 4 protons and 4 neutrons.
The original radioisotope would have an atomic number of 86+4 (protons), and would have an atomic mass of 222+8 (protons + neutrons). This would make the element Thorium-230, or 90Th230.