The increased and excessive use of automobiles and rapid growth of Industrial establishments post-industrial revolution era has contributed to the tremendous rise of pollution. The oxides of carbon, sulphur and nitrogen emission from vehicle exhaust and in the industrial process due to incomplete combustion of carbon compounds cause serious air pollution with other lethal gases release. The effluents from the industry that are toxic are released in the environment causing air pollution, noise pollution has become everyday routine with non-stop working of machinery and equipment, horns of car and engines harmful to people working around, establishments have caused deforestation leading to soil pollution.
Hence, the correct answer is 'Automobiles and indistries'.
Aerosols having carbon and fluorine compounds are chiefly released by _______.
The propellants used for jet engine release the halogenated paraffin compounds called fluorocarbons and chlorofluorocarbons. Both of these compounds are the potent ozone-depleting substances. Refineries, automobiles and industries release the oxides of carbon, sulphur and nitrogen.
The aircraft or jet planes engine emit certain particles and gases like carbon dioxide, hydrocarbons, nitrogen oxides, lead, black carbon, aerosols etc. These are basically greenhouse gases and anthropogenic compounds which have the tendency to react among themselves and with gases present in the atmosphere. Greenhouse effect, ozone depletion activities can be related to the emission of these gases.
Knocking refers to the sensitivity shown by the fuel such as petrol. Due to this, petrol has low pressure and temperature of ignition and tends to ignite before the actual ignition spark in the air. This has deleterious effects on the engine and poses a great risk. To prevent this, the antiknocking agents like methyl tertiary butyl ether, toluene etc. are added to the fuel. These agents increase the temperature and pressure required for ignition.
Hence, the correct answer is 'Explosion of unburnt fuel-air mixture'.