The term TYPE OF GAS can refer to a variety of different gases. TEAR is a type of gas composed of two oxygen atoms and one argon atom, commonly used in welding. NOBLE is a type of gas composed of five NOBLE gases, including helium, NEON, argon, krypton, and xenon. NERVE is a type of gas composed of nitrogen, oxygen, and rare gases, which is used in anesthesia. PROPANE is a type of gas composed of three carbon atoms and eight hydrogen atoms, which is used as a fuel for heating and cooking. METHANE is a type of gas composed of one carbon atom and four hydrogen atoms, which is a major component of natural gas. NEON is a type of gas composed of one NEON atom, which is used in lighting. INERT is a type of gas composed of five NOBLE gases, which is used in fire extinguishers. HIGHTEST is a type of gas composed of eight hydrogen atoms and one oxygen atom, which is the most flammable of all gases.