객관식How many unpaired electrons does a sulfur (S) atom have in its ground state electron configuration?167views
객관식An atom of phosphorus (atomic number 15) is in its ground state. How many valence electrons does this atom have?128views
객관식How can you determine the number of covalent bonds that atoms of an element can typically form?182views
객관식An atom has 15 total electrons. How many electrons does it have in its outer (valence) shell?146views