Which of the following techniques is used to determine the concentration of odour compounds in the given water sample?

(a) Settling

(b) Flushing

(c) Stripping

(d) Chlorination

(c) Stripping

Among the given options, stripping is the technique used to determine the concentration of odour compounds in a water sample.¹

Many of the compounds that cause odours in water are volatile, meaning they can easily turn into a gas. The process of air stripping involves bubbling air through the water. This causes the volatile odour compounds to move from the water into the air bubbles, effectively "stripping" them from the sample.²

In a laboratory setting, a similar technique called purge and trap is used.³An inert gas is bubbled through the water sample to strip the odour compounds, which are then trapped and concentrated.⁴ These concentrated compounds can then be analyzed, often with an instrument called a gas chromatograph, to identify them and measure their exact concentration.

The other options are incorrect:

• Settling is used to remove suspended solids.
• Flushing is a method for cleaning pipes.⁵
• Chlorination is a chemical process used for disinfection.⁶