What is the relationship between relief and topography?

Topography is the study of the shape and features of the surface of the Earth and other observable astronomical objects including planets, moons, and asteroids. ... This meaning is less common in the United States, where topographic maps with elevation contours have made "topography" synonymous with relief.

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