Which of the following describes a nuclear fusion reaction?     A.A much smaller particle breaks off from the nucleus of a heavy atom.   B.An electron and a proton combine to produce a neutron, dropping the atomic number.   C.Two nuclei with low mass combine to form one larger nucleus.

Definition Definition Number of protons in the nucleus of an atom. It uniquely identifies an element, as the number of protons determines the element's properties. The periodic table of elements is arranged based on increasing atomic numbers, allowing scientists to easily locate and study elements.