The map shows the geographic regions of the United States. In which US geographic region is South Dakota located?

the Mid-Atlantic
the Great Plains
the Southwest
the Southeast

So  if  the sum of the enthalpies of the reactants is greater than the products, the  reaction  will be  exothermic.  if  the products side has a larger enthalpy, the  reaction  is  endothermic. you may wonder why  endothermic reactions, which soak up energy or enthalpy from the environment, even happen