The first four ionization energies for an imaginary element, Xz are E1 = 102 kcal, E2 = 186 kcal, E3 = 4,021 kcal, and E4 = 4,862 kcal. The number of valence electrons most probable as indicated by this ionization data is:

Asample of silver (with work function ? = 4.52 ev) is exposed to an ultraviolet light source (? = 200 nm), which results in the ejection of photoelectrons. what changes will be observed if: silver is replaced with copper (? = 5.10 ev) more photoelectrons ejected no photoelectrons are emitted fewer photoelectrons ejected more energetic photoelectrons (on average) less energetic photoelectrons (on average)

Write a paragraph that provides examples of each stage of volcanic activity, a description of the volcano, and facts about each stage.

What are the first three quantum numbers for the electrons located in subshell 2s?