Test tube A and B contained adultered and non adulterated turmeric powders respectively. When concentrated HCl was added to both A and B, only one of the test tube changed its colour to red. Select the possible conclusion(s) associated with this experiment.

Metanyl yellow was present in A

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Chalk powder was present in A

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Solution in B changed red

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(a) and (c) above.

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Solution

The correct option is A Metanyl yellow was present in A
$∙$ Adulterants are the substances which are added to the natural foods and reduce its quality.
$∙$ Metanyl yellow, due to its similarity in colour and texture, is the commonly found adulterant in turmeric powder. To test its presence, it is mixed with water and concentrated HCl.
$∙$ The colouration of solution to red indicates the presence of metanyl yellow as an adulterant. As a result, only test tube A will change its colour to red.

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