One of the most widespread environmental carcinogens (cancer causing agents) is benzo[a]pyrene (molar mass of 252.30 g/mol). It is found in coal dust, cigarette smoke, and even charcoal-grilled meats. Analysis of this hydrocarbon shows that it is 95.21 % C and 4.79 % H. What is the molecular formula of benzo[a]pyrene?

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)

Explain which group an element with the electron configuration 1s2 2s2 2p6 3s2 3p6 3d1 4s2 belongs to.

21. consider the following chemical reaction: n2+ o2 2 no if 10.0 g of n2 reacts with excess oxygen then how many grams of no can be formed? a) 10.7 g b) 21.4 g c) 32.9 g d) 42.8 g page 4 of 8