Litmus paper is a type of indicator paper that changes color in response to changes in pH. Red litmus paper turns blue in the presence of an alkaline solution, while blue litmus paper turns red in the presence of an acidic solution.
Phenolphthalein is another type of indicator that changes color in response to changes in pH. It is colorless in acidic solutions and turns pink in alkaline solutions.
Congo red is a dye that changes color depending on the pH of the solution it is in. It is red in acidic solutions, blue in alkaline solutions, and purple in neutral solutions.
Based on the pH of bile, it can be predicted that:
* Litmus paper: Bile will turn red litmus paper blue.
* Phenolphthalein: Bile will turn phenolphthalein colorless to pink.
* Congo red: Bile will turn Congo red blue.
