a liquid.alicyclic hydrocarbon a hydrocarbon with carbon atoms joined together in a ring structure.aliphatic hydrocarbon answera hydrocarbon with carbon atoms joined together in straight or branched chains.acid answera species that is a proton donor.activation energy answerthe minimum energy required to start a reaction by the breaking of bonds.addition polymer answera very long molecular chain formed by repeated addition reactions of many unsaturated alkene molecules (monomers).addition polymerisation answerthe process in which unsaturated alkene molecules (monomers) add on to a growing polymer chain one at a time to form a very long saturated molecular chain (the addition polymer).addition reaction answera reaction in which a reactant is added to an unsaturated molecule to make a saturated molecule.adsorption answerthe process that occurs when a gas