2. Read the section above about electron configurations and consider the following electron configuration: [Ar] 4s² 3d a. How many core electrons are represented by this electron configuration? b. How many valence electrons are represented by this electron configuration? c. What element has this electron configuration?

Consider the eight most abundant elements in the human body, as outlined in Exercise 156. Excluding hydrogen, which of these elements would have the smallest size? largest size? smallest first ionization energy? largest first ionization energy?

Write electron configurations for the following elements. a. The Group III A element in the same period as 4Be b. The Period 3 element in the same group as 5B c. The lowest-atomic-numbered metal in Group IIA d. The two Period 3 elements that have no unpaired electrons

How many unpaired electrons are there 111 the following ions? (a) V3+(b) Sn4+(c) I-(d) W4+