Pronunciation: [blˈak smˈə͡ʊk] (IPA) 
Black smoke is spelled with the phonetic symbols /blæk sməʊk/. The first syllable "bl" is pronounced with a voiced "b" sound and a "l" sound, while the second syllable "ack" is pronounced with a short "a" sound and a voiceless "k" sound. The final syllable "smoke" is pronounced with a long "o" sound and a voiced "k" sound. The word refers to the dark, sooty smoke that is emitted from burning materials such as coal or wood.
Black smoke is a term commonly used to refer to a type of smoke that appears black or dark in color due to the presence of high concentrations of soot, carbon, or other particulate matter in the emitted gases. It is typically associated with incomplete combustion or burning of fuels, such as coal, oil, wood, or diesel, where the fuel does not receive sufficient oxygen during the combustion process.
The dark coloration of black smoke is a result of the absorption and scattering of light by the fine particles within the smoke. These particles are often extremely small, ranging from a few nanometers to a few micrometers in size, and are primarily composed of carbonaceous material. The high concentration of soot or carbon-based particles gives the smoke its distinctive black appearance, often observed rising from chimneys, exhaust pipes, or industrial facilities.
Black smoke may indicate inefficient or improper combustion, as the incomplete burning of fuel creates more harmful pollutants, such as carbon monoxide, nitrogen oxides, and fine particulate matter, which can have adverse effects on the environment and human health. Therefore, reducing the production of black smoke is crucial for minimizing air pollution and improving air quality. This can be achieved through various measures, including the use of cleaner-burning fuels, optimization of combustion processes, and implementation of emission control technologies.
The word "black" derives from the Old English word "blæc", which can be traced back to the Proto-Germanic word "blakkaz". This term eventually evolved into "black" in the English language, referring to the absence or darkness of color.
Similarly, the word "smoke" comes from the Old English word "smoca". It can be traced back further to the Proto-Germanic word "smukô", meaning "to smoke" or "to emit smoke".
When the words "black" and "smoke" are combined, they form the term "black smoke", indicating smoke that appears dark in color.
