Why does the number of valance electrons in Carbon provide such a useful atom?

What is the name of the two satelites on mars

Most of the fossils found in virginia are in the coastal plain, valley, ridge, and appalachian plateau regions, best suggesting that these geographic provinces a) were once covered by seawater. b) are the oldest parts of virginia. c) have a great deal of karst topography. d) have large amounts of sedimentary rock.

What is the difference between how ionic and covalent bonds form