The electron with its extra packet of energy becomes excited, and promptly moves out of its lower energy level and takes up a position in a higher energy level.
C & B are switched so I'm not sure if that was a typo or not, but the answer is concentration!
Answer:
english:
Solid is the state in which matter maintains a certain volume and shape; liquid is the state in which matter conforms to the shape of its container, but varies only slightly in volume; gas is the state in which matter expands to fill the volume and shape of its container.
español:
Sólido es el estado en el que la materia mantiene cierto volumen y forma; el líquido es el estado en el que la materia se adapta a la forma de su recipiente, pero varía sólo ligeramente en volumen; el gas es el estado en el que la materia se expande para ocupar el volumen y la forma de su recipiente.
