How many unpaired valence electrons are there for an element with the valence shell configuration ns2(n-1)d10np4 14 3 4 2

6.82 A particular element has the following values for its first four ionization energies: 900, 1760, 14, 850, and 21,000 kJ/mol. Without consulting a list of ionization energy values, determine what group in the periodic table this element belongs in.

6.84 Which graph correctly depicts the first ionization energy of three elements in groups 14 (dashed line) and 17 (solid line)? Explain the reasoning you used to make your choice.

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?

Arrange the following groups of atoms in order of increasing size. a. Rb, Na, Be b. Sr, Se, Ne c. Fe, P, O

Calculate the effective nuclear charge, Z, on these electrons in a tin atom (a) 5s; (b) 5p; and (c) 4d.

Using complete subshell notation ( 1s22s22p6, and so forth), predict the electron configurations of the following ions. (a) N3- (b) Ca2+ (c) S- (d) Cs2+ (e) Cr2+ (f)Gd3+

On which quantum numbers does the energy of an electron depend in each of the following? a. a one-electron atom or ion b. an atom or ion with more than one electron

Write one possible set of quantum numbers for the valence electrons of calcium.

The following numbers are the ratios of second ionization energy to first ionization energy: Na: 9.2 Mg: 2.0 Al: 3.1 Si: 2.0 P: 1.8 S: 2.3 Cl: 1.8 Ar: 1.8 Explain these relative numbers.