What is Smoke?
[[Image:Candle smoke structure 1.jpg|thumb|]] '''Smoke''' is a [[cloud]] of very small, solid particles that is made when something is [[burn]]ed with a [[flame]], such as wood or paper. Smoke can be bad because if it goes into the [[lung]]s of a person, it can hurt their lungs or even kill them (for example, in a house [[fire]]). Most people think that they are always able to see smoke, but people cannot see some types of smoke: they are [[wikt:invisible|invisible]]. Smoke removal systems redistribute gas flows and reduce the temperature and concentration of smoke during a fire. This helps in evacuating people, limiting the spread of fire; and extinguishing the fire.<ref>{{Cite web|title=Highrise building smoke removal|url=https://www.cityofsacramento.org/-/media/Corporate/Files/Fire/Guidebooks/Highrise-Smoke-Removal-System-Standard.pdf?la=en|website=Sacramento Fire Department}}</ref> <gallery> File:Defense.gov photo essay 100506-N-6070S-346.jpg|Oil fire File:2017-365-91 Smoking Candle (33401913500).jpg|Candle smoke Image:Smoke 123.jpg|Campfire in Africa Image:Ognisko ubt 0126.jpeg|Bonfire smoking </gallery> == Smoke from tobacco == [[File:Cigarette smoke.jpg|thumb|right|]] When people smoke [[tobacco]] in [[cigar]]s or [[cigarette]]s, they are burning the tobacco and inhaling the smoke. Tobacco smoke can hurt the mouth, throat, and lungs. It can cause mouth, throat, or [[lung cancer]]. It can also cause [[emphysema]] and [[bronchitis]] (trouble breathing). They continue doing it because the smoke also has a [[nicotine]]. == Smoke from factories == [[factory|Factories]] and [[power plant]]s produce large amounts of smoke into the atmosphere which [[pollution|pollutes]] the air. Eventually the toxic [[chemical]]s in smoke fall to the ground, and then they pollute the soil and the [[water pollution|water]]. When the air, soil and water are polluted with toxic chemicals, the chemicals also get absorbed by [[plant]]s and [[animal]]s (including [[human]]s). ==Related pages== *[[Carbon dioxide#Dry ice|Dry ice]] *