std 11 history annual exam blueprint & full paper solution April 2022 | dhoran 11 paper solution

Blue litmus paper turns on contact with an acidic solution.

In the preparation of ultra filter paper collodion solution is used collodion is

How does a soap solution behave with red litmus paper ?

When the strip of pH paper was put in a given solution the pH paper changes to orange red. The given solution is most likely to be of: