Consider the reaction:
2Mn(s) +O2(g) => Mn2O3(s);AH° = -959.0 kJ
Find AH for the following reaction:
2Mn2O3(s) => 4Mn(s) + 302(g)
+959.0 kJ
+1918 kJ
-3836 kJ
O-1918 kJ
+3836 kJ

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

Salt in oceans comes from and of rocks

Asubstance is held in an open container. its particles move past one another at random speeds but do not leave the container. heat is removed from the system, and the particles slow down. when enough heat is removed, the particles no longer have enough speed to overcome the weak attractive forces between them. when this happens, the substance enters its solid state. the process described above is known as .