Where to buy acid / base indicator solution?

[Analog]

Is this an item that can be bought easily? I know that photographic stop bath has this solution, but it also has acetic acid. Any thoughts?

 

[Billb2]

If you can use pH strips, most tropical fish stores have them.

Different test solutions will change color at different pHs. What pH are you looking for?

 

[Analog]

Originally posted by: Billb2
If you can use pH strips, most tropical fish stores have them.

Different test solutions will change color at different pHs. What pH are you looking for?

I wanted to use a solution for a more dramatic effect than paper. This is for kids to see a color change when mixing mild acids and bases. Not for extreme ph solutions, just for kids.

 

[BrokenVisage]

*waits for the "Where to buy LSD / freebase solution" parody*

 

[silverpig]

Fish stores will have the strips which should work well for you.

 

[AMCRambler]

Fish stores also have the solutions for testing. Supposedly more accurate than the strips. I buy the Red Sea test kits for my fish tank. I'm not sure what the solution is for the PH test but I don't think it's phenolthalene. If I remember right phenolthalene turns pink or blue depending on the PH. The stuff that comes in the Red Sea kit turns purple for the base end of the scale and greenish gray/yellow for the more acidic end. I think it only measures PH at 7 or higher though. I think that 7 is as low as the card's color chart goes. So strips might be the only thing they carry that would work for you.

 

[jdobratz]

Red cabbage can act as an acid/base indicator if you cant find anything better. Get a head of it, chop it up and boil it in water for awhile. Strain the resulting liquid and have fun.

http://www.york.ac.uk/res/sots/activities/acidtest.htm

 

[Analog]

Originally posted by: jdobratz
Red cabbage can act as an acid/base indicator if you cant find anything better. Get a head of it, chop it up and boil it in water for awhile. Strain the resulting liquid and have fun.

http://www.york.ac.uk/res/sots/activities/acidtest.htm

That seems like a safe way to go, thanks.

 

[uclaLabrat]

I believe phenolpthalein is the active ingredient in ex-lax. Have fun!