Calculate ho298 for the process co3o4 ? 3co + 2o2 from the following information:
co + 1/2o2 -> coo ho298 = -237.kj
3co + o2 -> coo4 ho298 = -177.5kj

Y=‐1x + 7 if y has a value of ‐24 what is the value of x?

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

Answer explain why it is not possible to deduce a complete order of reactivity.