Despite the expected decrease in atomic size, there is an un-expected drop in the first ionization energy between Groups2A(2) and 3A(13) in Periods 2 through 4. Explain this pattern interms of electron configurations and orbital energies.

Due to periodicity, which element would you expect to behave most like molybdenum? (a)   Tungsten              (b)    Titanium            (c)    Manganese         (d)    Niobium

Give the valance electron configuration for Niobium.

Which of these ionization processes requires the most energy?           (A) Na(g)  -->  Na+(g)  +  e–;          (B) K(g)  -->  K+(g)  +  e–;          (C) Mg(g)  -->  Mg+(g)  +  e–;          (D) Al(g)  -->  Al+(g)  +  e–;

Which of the following has the smallest ionic radius? (A) p3- (B) K1+ (C) Sc3+ (D) Ar 7.

In a plot of IE1 for the Period 3 elements , why do the values for elements in Groups 3A(13) and 6A(16) drop slightly below the generally increasing trend?

Nitrogen has a greater first ionization energy than phosphorus. What is the best evidence to supportthis observation?

The ionization energy of lithium is 520.2 kJ/mole, and the electron affinity of hydrogen is 72.8 kJ/mole.(a) Find the separation distance in LiH at which the Coulomb potential energy equals the energy cost of removing an electron from Li and adding it to H.(b) The measured electric dipole moment of the molecule LiH is 2.00 × 10^−29 C · m. What is the fractional ionic character of LiH?(c) Instead of removing an electron from Li and attaching it to H, we could regard the formation of LiH as occurring by removing an electron from H and attaching it to Li (electron affinity = 59.6 kJ/mole). Why don’t we consider this as the formation process?

Write a balanced equation for the reaction that occurs in each ofthe following cases: (a) Chlorine reacts with water. (b) Bariummetal is heated in an atmosphere of hydrogen gas. (c) Lithiumreacts with sulfur. (d) Fluorine reacts with magnesium metal.

What is the characteristic valence electron configuration of the group 7A elements, the halogens?