What are some observable indications that a chemical reaction has occurred?

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

Describing intermolecular forces use the drop down menus to match the type of intermolecular force to its name dipole dipole interactions dipole induced dipole interactions london dispersion forces hydrogen bond van der waals forces done

Name the element in group 17, period 2. (periodic table)