Given below are two statements. In the light of the above statements, choose the most appropriate answer from the options given below.
Statement I:Fuel oxides of nitrogen (NOx) are created when nitrogen and oxygen in the combustion chamber are heated to as high as 1000 degrees Celsius.
Statement II:Thermal NOx is often the dominant source in the total NOx emissions.
ABoth Statement I and Statement II are correct
BBoth Statement I and Statement II are incorrect ✓ Correct
CStatement I is correct but Statement II is incorrect
DStatement I is incorrect but Statement II is correct
Correct answer: (B) Both Statement I and Statement II are incorrect
Explanation
Both statements are incorrect about how nitrogen oxides form in combustion.
Statement 1 is wrong, because heating combustion air nitrogen and oxygen makes thermal NOx, not fuel NOx.
Fuel NOx instead comes from nitrogen chemically bound within the fuel itself.
The stated 1000 degree threshold is too low, as thermal NOx forms mainly above 1300 degrees.
Statement 2 is wrong, because fuel bound nitrogen, not thermal NOx, often dominates in coal combustion.
Reducing peak flame temperature and staging air are common ways to curb NOx.
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