Types of Anxiety Disorders The black exhaust Black seems to be a depressing color. The reason must be rich mixture. That is to say, the amalgamation of gas in cylinder component is at night normal level. The incomplete combustion gas inside combustion chamber result in the carbon particle exhausted with the waste gas. Failure is likely to come from the following reason: Plasma can often be called the fourth state of matter, after solid, liquid, and gas. It is also sometimes described as an ionized gas i.e. a gas when the degree of energy is really high how the electrons escape from the atoms. This leads to soups of charged particles that happen to be overall quasi-neutral.