What is the largest source of sulfur dioxide air pollution? a. transportation b. the greenhouse effect c. burning fossil fuels in vehicles, power stations, and factories d. construction, agriculture, and unpaved roads select the best answer from the choices provided?

the number of valence electrons for each molecule or ion is shown beneath the structure. remember hydrogen will not have more than two electrons. this hydrogen is part of a covalent bond (sharing two electrons). a double bond here would cause hydrogen to share four electrons with phosphorus.