No, the energy absorbed by an atom does not continue to travel at the speed of light (C) within the atom. When an atom absorbs energy in the form of a photon, the photon is essentially absorbed by an electron within the atom, promoting it to a higher energy state. This process is known as electronic excitation.
Within the atom, the absorbed energy is converted into potential energy of the electron in its excited state. The excited electron can then undergo various processes, such as emitting a photon and returning to a lower energy state (known as spontaneous emission) or transferring its energy to another atom or molecule through collisions (known as collisional de-excitation).
In either case, the energy absorbed by the atom is typically transferred to other particles or converted into other forms of energy within the atom or its surroundings. The speed at which this energy is transferred or converted is not necessarily equal to the speed of light. It depends on various factors and processes occurring within the atom and its environment.