What are scientific questions based on

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)

Many ionic compounds and a few highly polar covalent compounds are because they completely ionize in water to create a solution filled with charged ions that can conduct an electric current.

The number of moles of a given mass of a substance can be found without knowing its molecular formula or molar mass. true false