For a research project on time management, Yuri needs to calculate how many hours the average high school student spends in school each year. Which of these dimensional analysis equations is the correct one for him to use?

1)each group 16 element has how many valence electrons? ( )4 ( )6 ( )8 ( )16 2)how many dots appear in the dot structure for calcium ion, ca2+? ( )zero ( )one ( )two ( )eight 3) which of the following atoms forms a cation to obtain an octet of outer shell electrons? ( )magnesium ( )oxygen ( )fluorine ( )helium 4) an al3+ ion contains 13 protons and 10 electrons. ( )true ( )false 5) valence and non-valence electrons are represented in lewis dot structures. ( )true ( )false

Draw the skeletal structures of two different molecules that are each made of 5 carbon atoms and 12 hydrogen atoms.

An object becomes electrically charged when: electrons are created in it electrons from it are destroyed electrons are transferred to it protons from it are destroyed protons are created in it