In terms of energy produced during combustion, which butane conversion yields the highest energy output per gram?

The conversion of butane that yields the highest energy output per gram is combustion. During combustion, butane reacts with oxygen to produce carbon dioxide and water, releasing a significant amount of energy in the form of heat and light. This process is highly exothermic, meaning that it produces more energy than it consumes.

In the case of combustion, the breaking of chemical bonds in butane and oxygen releases energy that is stored in the products (carbon dioxide and water). The overall reaction has a large negative enthalpy change because the bonds formed in carbon dioxide and water are much stronger than those in the reactants. This strong exothermic nature of combustion is why it is used as a primary means of energy production, such as in internal combustion engines and heating systems.

Other options, like fermentation, mainly involve the conversion of sugars to alcohol and carbon dioxide, yielding significantly less energy compared to combustion. Oxidation reactions can release energy as well, but they do not typically achieve the high levels of energy output characteristic of combustion. Addition reactions, while important in organic chemistry, do not generally lead to substantial energy releases like combustion does. Hence, combustion is recognized as the most efficient method for producing energy from butane on a per gram basis.