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.
Combustion is a chemical reaction that produces heat and light. The most common form of combustion is fire. Most forms of combustion happen when the gas oxygen joins with another substance.For example, when wood burns, oxygen in the air joins with carbon in wood.ombustion is a chemical reaction that produces heat and light. The most common form of combustion is fire. Most forms of combustion happen when the gas oxygen joins with another substance.