Question

A student was given two test-tubes A and B each containing a colourless solution. When a few drops of universal indicator were added to the two test-tubes, one by one, then the colour of solution in test-tube A changed to blue whereas the colour of solution in test-tube B changed to orange.
(a) Which test-tube has a solution of pH higher than 7?
(b) Which test-tube has a solution of pH lower than 7?
(c) Which test-tube has an acidic solution?
​(d) Which test-tube has an alkaline solution?

Answer 1

Answer:

a) test tube A

b) test tube B

c) test tube B

d) test tube A

hint:

in acidic solution, blue litmus change to red colour.

in basic solution, red litmus change to blue colour.

PH is less than 7 for acidic solution.

PH is greater than 7 for basic solution.