How do valence electrons determine a elements chemical properties?

One of the few xenon compounds that form is cesium xenon heptafluoride (csxef7). how many moles of csxef7 can be produced from the reaction of 13.0 mol cesium fluoride with 12.5 mol xenon hexafluoride? csf(s) + xef6(s) csxef7(s)

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

How do you identify the anode on a power source such as a battery? how do you identify the cathode? how are terms anion and cation?