A panic attack is an exaggeration of your bodyâs normal response to fear, stress or excitement. It is the rapid build-up of overwhelming physical sensations, such as: 1  a pounding heartbeat. 2  feeling faint. 3  sweating. 4  nausea (feeling sick).
Since four elements must be present for the combustion process to occur (fuel, heat, an oxidizing agent, and a chemical chain reaction), a fire can be extinguished by removing any one of these four elements.
A combustion reaction is a major class of chemical reactions. Combustion usually occurs when a hydrocarbon reacts with oxygen to produce carbon dioxide and water. In the more general sense, combustion involves a reaction between any combustible material and an oxidizer to form an oxidized product. Combustion is an exothermic reaction, so it releases heat, but sometimes the reaction proceeds so slowly that a temperature change is not noticeable. Good signs that you are dealing with a combustion reaction include the presence of oxygen as a reactant and carbon dioxide, water and heat as products.