Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R). Assertion (A): Clothes containing oil or grease stains cannot be cleaned by water wash. Reason

Question

Given below are two statements: One is labelled as Assertion (A) and the other is labelled as Reason (R).

Assertion (A): Clothes containing oil or grease stains cannot be cleaned by water wash.

Reason (R) : Because the angle of contact between the oil/ grease and water is obtuse. In the light of the above statements, choose the correct answer from the option given below.

TestHub · Accepted Answer

Angle of contact between oil and water is obtuse i.e., greater than critical angle of contact $(θ c > 90 °)$ , therefore they do not stick and that's the reason grease/oil stains can not be removed by water wash.
Thus, both (A) and (R) are true and (R) is the correct explanation of (A).

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