Sciencemadness Discussion Board

pH paper: 1 colour vs multicolour?

fusso - 31-3-2019 at 08:02

I've seen 2 types of pH paper, 1 is the plain yellow coloured strip, another is a few patches on the same strip, and different patches will turn into different colours when dipped into the same solution.
Which is superior?

SWIM - 31-3-2019 at 08:26

I've never even seen either of those.

How about pink?
Or blue?
Or that Hydrion wide range multi-color stuff?

fusso - 31-3-2019 at 08:38

This is the multicolour I'm talking about :

draculic acid69 - 31-3-2019 at 08:43

Those ones are generally used for swimming pools and stuff.get both for improved accuracy.

Sulaiman - 31-3-2019 at 10:03

One difference is that the cheap pH 1-14 papers that I use react to just one drop of sample liquid,
and a small piece can be dropped in a beaker/flask/test tube.

Ubya - 31-3-2019 at 12:37

with universal ph paper (the yellow one)you usually add 1 drop of solution to the paper, while the other kind is dipped in the solution.
i don't know which is more accurate (they also sell "universal ph paper" but for narrower ph intervals to be more accurate with your measuring), butin general would be better to bring a drop of the sample to the ph paper and not dip the paper in the solution (to avoid contamination, yea i know is minor but is a good habit)

CharlieA - 31-3-2019 at 16:54

I don't see much difference between applying a drop to the paper (which is 1 color before being placed in contact with the test solution) or the paper to the solution, except for the possibility of contamination as Ubya stated above (ciao, senore). Bringing a drop to the paper is best practice.