Help, Please, with Ph Indicators

[imp]

Would someone be willing to explain the common indicators for Ph of solutions? For example, does Litmus paper simply indicate QUALITATIVELY that a solution is either above or below 7.0 PH? Or is there some degree of QUANTITATIVE amount of color-change?

 

How is Phenolphthalein paper used?

 

And finally, my Ph-indicating paper changes color immediately, as the liquid proceeds upward through the test paper, but the color returns to original paper color, more or less orange, behind the advancing wetted area, which does change color for a short time, but then returns to orange. The instructions say check color within 30 seconds. Trouble is, within 10 seconds, the whole test strip has returned to original color. Any ideas?

 

Thank you in advance!! imp

[thedarkshade]

Perhaps you might find anything on the links below:

 

http://en.wikipedia.org/wiki/Litmus_paper

http://en.wikipedia.org/wiki/Phenolphthalein

http://en.wikipedia.org/wiki/Methyl_orange

 

If you think that I'm not really helping by just posting links, that'd be as a result of feeling sleepy.

[imp]

Dark, thank you for responding. Reason I ask such questions is that searching internet takes forever with the slow dial-up service I am stuck with.

 

No DSL available here; even cell phones are dead! imp