Homework problem 2.1 (d) [ENDORSED]

[tatianatumbling_1J]

D on this problem asks if radius increases as atom goes from 1s to 2p. I answered no, it decreases because atomic radius decreases from left to right on the periodic table. However the solution manual says radius increases because it is related to n... can someone explain?

[NatalieSDis1A]

I answered that the radius increases because when we move from 1s to 2p we are increasing the size of the probability function. The books says this "the average distance of an electron from the nucleus when it occupies any of the orbitals in the shell with n = 2 is greater than when n = 1, and so we can think of the atom as swelling up as it is excited energetically."

[Jacy Black 1C]

The more electrons and the more sub shells inhabited, the larger the atomic radius. If you think of the sub shells as expanding outwards from the nucleus, then the more sub shells that are inhabited, the larger the atom itself. In a very simple example, its like the more electrons orbiting the nucleus, the "fatter" the atom is. If you think of the very simple diagram where each orbital is a circle around the nucleus, this example makes more sense.