The gram atomic mass of oxygen is 16.0 grams per mole. How many atoms of oxygen does this mass represent?

What’s the percent by mass of carbon in c10h14n2

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

How many grams of magnesium metal will react completely with 8.3 liters of 5.5m hcl? show all work