Question

Gases emit radiation under which of the following conditions which can be used for determination of gases?

(a) When mixed with other gases

(b) When kept at suitable temperature

(c) With sufficient electrical excitation and at suitable pressures

(d) When exposed to radiation

This question was posed to me in a job interview.

The doubt is from Method Based on Ionization of Gases in portion Industrial Gas Analysers of Analytical Instrumentation

Answer 1

The correct option is (c) With sufficient electrical excitation and at suitable pressures

For explanation: Gases emit radiation with sufficient electrical excitation and at suitable pressures. Gases emit radiation in different ways. It can be in the form of spark, arc or glow discharge in different parts of the radiation spectrum.