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.
PM Images, Getty Images. Combustion Reaction Definition: A combustion reaction is a type of chemical reaction where a compound and an oxidant is reacted to produce heat and a new product. Examples: 2 H 2 + O 2 â 2H 2 O + heat and. CH 4 + 2 O 2 â CO 2 + 2 H 2 O + heat are both combustion reactions.M Images, Getty Images. Combustion Reaction Definition: A combustion reaction is a type of chemical reaction where a compound and an oxidant is reacted to produce heat and a new product. Examples: 2 H 2 + O 2 â 2H 2 O + heat and. CH 4 + 2 O 2 â CO 2 + 2 H 2 O + heat are both combustion reactions.