Describe what you know about Elements, Compounds, and Mixtures, how the Periodic table is used, and how any of this may be relevant to scientists or in our daily life.

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)

This is a mixture that has the same composition throughout.

How many moles of air are there in a human lung with a volume of 2.4 l at stp? explain your answer