What is the term used for the elements and compounds after a chemical reaction takes place?

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)

According to the vsepr theory what is the shape of a molecule that has a central atom valence three other items with no lone pairs of electrons

What will most likely happen when two bromine atoms bond together?