Where could you find hydrocarbon chains?

Most Hydrocarbon chains are found in petroleum, coal, and natural gas. First of all, a hydrocarbon chain is a molecule that consist of entirely hydrogen and carbon.

Explanation: There are many types of hydrocarbon chains, which can be found in alkanes, alkynes, arenes, alkenes, and cycloalkanes. Natural rubber for instance is a hydrocarbon that primarily consists of alternating single and double bonded carbons.

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.