Anewly isolated natural product was found to have the molecular formula c15h28o2. by hydrogenating a sample of the compound, it was determined to possess one π bond. how many rings are present in the compound?

2. how is heavy water different from normal water

How many moles of air are there in a human lung with a volume of 2.4 l at stp? explain your answer

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