Question 123 of 192

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.

ABoth (A) and (R) are true and (R) is the correct explanation of (A)BBoth (A) and (R) are true but (R) is not the correct explanation of (A)C(A) is true but (R) is falseD(A) is true but (R) is true

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Answer: (A) Both (A) and (R) are true and (R) is the correct explanation of (A)

Angle of contact between oil and water is obtuse i.e., greater than critical angle of contact $\left(\theta c\gt 90^{\circ}\right)$, 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).