A solution has a pOH of 12.4. What is the pH of this solution?

Explain why scientists use shared characteristics to make cladograms.

Consider the following system at equilibrium. caco3(s) ca2+(aq) + co32–(aq) the addition of which compound will cause a shift in equilibrium because of a common ion effect? ccl4 co2 cuso4 na2co3

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