A map of the world is shown below. The southeast coast of North America and the northwest coast of Africa are highlighted in red. Consider the southeast coast of North America and the northwest coast of Africa. According to the current theory of plate tectonics, these two regions were once very close together. However, the coasts do not quite fit together like puzzle pieces, as one might expect. This can be explained by the fact that the southeast edge of North America's actually does fit nicely with the northwest edge of Africa's even if the coasts do not.

the correct answer is:

a. formation of precipitation

a. energy is absorbed in the reaction.

if in a given reaction the energy of products is greater than the energy of reactants it means that reaction is endothermic and during the reaction, the energy is absorbed by reactants. in an endothermic reaction, the products have more stored chemical energy than the reactants. and in this reaction the reactants are more stable than products before the compounds with less energy are always more stable.

chemical changes occur when a substance combines with another to form a new substance, called chemical synthesis or, alternatively, chemical decomposition into two or more different substances. these processes are called chemical reactions and, in general, are not reversible except by further chemical reactions. some reactions produce heat and are called exothermic reactions and others may require heat to enable the reaction to occur, which are called endothermic reactions. understanding chemical changes is a major part of the science of chemistry.