litmus paper
Example Sentences
Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.
The best way to confirm that the solution is neutralized is with litmus paper.
From Seattle Times • Nov. 7, 2022
Watson recalls one telling advertising campaign: posters printed on litmus paper that said: “When acid rain is falling, you should see red” – offering a vivid illustration of the problem.
From The Guardian • Oct. 12, 2020
Peterson's guide also played a role in creating today's environmental awareness; as he explains, birds act as a kind of "ecological litmus paper," reacting to changes in their surroundings long before man does.
From Time Magazine Archive
But that is not an immutable piece of parchment that judges can apply to laws like litmus paper.
From Time Magazine Archive
So, to test for a base, use a piece of litmus paper that is pink and see if it turns blue, or if you want to test for an acid, use blue litmus paper.
From Common Science by Ritchie, John W. (John Woodside)
