Here is a sketch of the radial probability distribution of three orbitals: 0.0020 probability 0.0015 0.0010- 0.0005 500 1000 1500 2000 2500 3000 distance from nucleus (pm) Use this sketch to answer the following questions. What is the most likely distance from the nucleus for an electron in orbital A? Note: your answer must be within 50 pm of the exact answer to be graded correct. List the orbitals in order of increasing energy: Suppose all three orbitals were inner orbitals of an atom. In which orbital would an electron be most effective at screening the charge of the nucleus from the outer electrons? ☐ pm (choose one) -B 0,0.... G

The energies of macroscopic objects, as well as those of microscopic objects, are quantized, but the effects of the quantization are not seen because the difference in energy between adjacent states is so small. Apply Bohr’s quantization of angular momentum to the revolution of Earth (mass6.01024kg) , which moves with a speed of 3.0104ms1 in a circular orbit (radius1.51011m) about the sun. The sun can be treated as fixed. Calculate the value of the quantum number n for the present state of the Earthsun system. What would be the effect of an increase in n by 1?

• identify an orbital (as 1s, 3p, etc.) from its quantum numbers, or vice versa.

Use the mathematical expression for the 2pz wave function of a one-electron atom (see Table 5.2) to show that the probability of finding an electron in that orbital anywhere in the x-y plane is 0. What are the nodal planes for a dxz orbital and for a dx2y2 orbital?