the youngest layer is 7(middle point) because decomposition must occur in the middle of decomposed materials.the oldest is 12(upper one) because decomposed material are found at the top most of organisms.
<span>We know that electrons are occupied on a cloud surrounding
the nucleus. So which means that the bigger the electron cloud, the bigger the
number of electrons. So in this case, since Na shrank so it lost some
electrons. And since Cl+ grew in size of the electron cloud so electron was
added to it.</span>
