Final answer:
Transferring an electron from sodium to bromine is an example of a redox reaction where sodium is oxidized and bromine is reduced. Sodium's oxidation number increases, and bromine's decreases, in this electron transfer with associated energy change.
Step-by-step explanation:
The question involves the transfer of an electron from a sodium atom to a bromine atom. This process is an example of a redox reaction, where sodium is being oxidized and bromine is being reduced. When an electron is transferred, sodium’s oxidation number increases from 0 to +1, indicating a loss of an electron and undergoing oxidation. Concurrently, bromine’s oxidation number decreases from 0 to -1 when it gains an electron, indicating reduction. The energy change associated with this electron transfer is related to the ionization energy of sodium and the electron affinity of bromine.
The change in energy can vary depending on the specific conditions and compounds involved, but the concept remains that sodium loses an electron, which is then gained by bromine. Since the oxidation numbers are changing, it confirms that a redox reaction is taking place. For every sodium atom in this reaction, two sodium ions are created, and for every bromine molecule, two bromide ions are generated, thereby maintaining the balance of electrons transferred.