Question

Which of the following is the wavelength of the radiation generated when an air stream containing sulphur dioxide is burned in a hydrogen-rich flame?

(a) 243 nm

(b) 394 nm

(c) 467 nm

(d) 516 nm

I have been asked this question by my school principal while I was bunking the class.

Origin of the question is Sulphur Di-oxide Monitoring topic in division Pollution Monitoring Instruments of Analytical Instrumentation

Answer 1

Right option is (b) 394 nm

The explanation is: The wavelength of the radiation generated when an air stream containing sulphur dioxide is burned in a hydrogen-rich flame is 394 mm. A narrow band interference filter is used to shield radiations with all other wavelengths.