Question

Assertion: Sulphide ores are concentrated by Froth Flotation method.

Reason: Cresols stabilise the froth in Froth Flotation method.

• A. Assertion is true but reason is false.
• B. Both assertion and reason are true and reason is the correct explanation of assertion.
• C. Both assertion and reason are true but reason is not the correct explanation of assertion.
• D. Assertion and reason both are wrong.
• E. Assertion is false but reason is true.

Answer 1

The correct option is C Both assertion and reason are true but reason is not the correct explanation of assertion.

$\text{Analysing assertion}$

Sulphide ores are concentrated by froth flotation method because sulphide ores particles are preferentially wet by adsorption on collectors (e.g., pine oils, fatty acids, xanthates, etc.) and impurities are preferentially wet by water.

So, the assertion is correct.

$\text{Analysing reason}$

Froth stabilizers (e.g., cresols, aniline) stabilizes the froth in froth floatation method.

So, reason is also correct but it does not explain the assertion.

Hence, both assertion and reason are true but reason is not the correct explanation of assertion.