Some areas of the earth receive more solar radiation than others. what is an example of the sun’s uneven heating of the earth

Earth's orbit around the sun and its rotation on a tilted axis causes some parts of Earth to receive more solar radiation than others. This uneven heating produces global circulation patterns. For example, the abundance of energy reaching the equator produces hot humid air that rises high into the atmosphere

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