Naked Science Forum

Non Life Sciences => Chemistry => Topic started by: samthekiwi on 15/07/2021 03:02:15

Title: How to colour an acidic liquid?
Post by: samthekiwi on 15/07/2021 03:02:15

Hello,

I am currently working on a liquid cleaning product and I want it to be blue. The liquid has a PH of 3-4 meaing it is mildy acidic. I have tried food colouring and it will change the colour to blue however overnight the acid in the liquid is then changing it back to white.

Can anyone recommend a colouring ink or dye that will work with an acidic liquid?

Cheers,
Sam

Title: Re: How to colour an acidic liquid?
Post by: Bored chemist on 15/07/2021 13:22:00

https://en.wikipedia.org/wiki/Methylene_blue
is fairly acid stable.