Electrons can gain the energy it needs by absorbing light. If the electron jumps from the second energy level down to the first energy level, it must give off some energy by emitting light. The atom absorbs or emits light in discrete packets called photons, and each photon has a definite energy.
C. The number of protons in the atoms nucleus.
<span>The outer electrons are not as tightly bound as ones closer to the nucleus</span>
A is correct. water is incompressible, so it will always have the same density, regardless of volume
