2 mL of ethanoic acid was taken in each of test-tube I and test-tube II. A red litmus paper was introduced in test-tube I and a pH paper was introduced in test-tube II. The experiment was performed by four students A, B, C and D, they reported their observations as given below :

Student
Action on red litmus

Action of pH paper

A
B
C
D
Turned blue
Remains unchanged
Turned blue
Remains unchanged

Turned pink
Turned green
Turned blue
Turned pink

The correct set of observations was made by the student :
(1) A
(2) B
(3) C
(4) D

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Solution

As ethanoic acid is an acid, it will convert blue litmus to red. So, observation of student D on the action of litmus is correct as red litmus remain unchanged and pH paper will turn pink(because it is a weak acid).

Hence, the correct answer is option 4.

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Similar questions

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Student	Action on red litmus	Action of pH paper
A B C D	Turned blue Remains unchanged Turned blue Remains unchanged	Turned pink Turned green Turned blue Turned pink

As ethanoic acid is an acid, it will convert blue litmus to red. So, observation of student D on the action of litmus is correct as red litmus remain unchanged and pH paper will turn pink(because it is a weak acid). Hence, the correct answer is option 4.

As ethanoic acid is an acid, it will convert blue litmus to red. So, observation of student D on the action of litmus is correct as red litmus remain unchanged and pH paper will turn pink(because it is a weak acid).

Hence, the correct answer is option 4.