EVERYDAY SCIENCE

Detailed explanation-1: -A combustion reaction will always occur when a substance reacts with oxygen to release energy. For example, when methane burns in oxygen, it releases carbon dioxide and water. The formation of carbon dioxide shows the carbon present in the methane has undergone oxidation.

Detailed explanation-2: -Combustion reactions must have oxygen as a reactant. Note that the water produced is in the gas state, rather than the liquid state, because of the high temperatures that accompany a combustion reaction.

Detailed explanation-3: -Combustion reactions always involve molecular oxygen O2. Anytime anything burns (in the usual sense), it is a combustion reaction. Combustion reactions are almost always exothermic (i.e., they give off heat).

Detailed explanation-4: -A combustion reaction is a chemical reaction in which a fuel undergoes oxidation by reacting with an oxidising agent, resulting in the release of energy (usually in the form of heat).

Detailed explanation-5: -Combustion reaction is a reaction in which a substance reacts with oxygen gas, releasing energy in the form of light and heat. Combustion reactions must involve O2 as one reactant. The products of the combustion of hydrocarbons are carbon dioxide and water.