Which of the following compounds has an expanded octet around the central atom when the best Lewis Structure is drawn for it?

Which of these statements best describes why Group 8 elements (such as Ar) have smaller (more positive ∆H) electron affinities than other elements?

Which of the following oxyanions has only two equivalent resonance structures?

Which of the following elements has the highest Electron Affinity (most negative ∆E)?

Carbon exists in different elemental forms in nature, including diamond and graphite. These two forms of carbon are examples of                                .

Which of the following elements has the largest 2nd ionization energy (IE2)?

Three possible Lewis structures are shown below for the thiocyanate ion, SCN-: Which of these Lewis Structures is/are the most favorable?  (Note: N is more electronegative than S)

Which of the following elements has the largest 1st Ionization Energy (IE1)?

What is the formal charge on the singly-bonded oxygen atom in the resonance structure of H2SO4 below?

What is the oxidation number of each oxygen atom in the compound, potassium peroxide?