A universal indicator is a solution which undergoes several color changes over a wide range of pH's. 
The pH curve for the strong acid-weak base titration shows that phenolphthalein is not a suitable indicator but methyl orange is fine. For the titration of weak acid-strong base, phenolphthalein, but not methyl orange, is a suitable indicator. Acids & bases. Vocabulary anthocyanin acid alkaline base indicator pH solution universal indicator A universal indicator is a solution which undergoes several color changes over a wide range of pH's. The color is used to indicate pH directly. Universal indicators are usually mixtures of several indicators. The easiest universal indicator to prepare is red cabbage juice. Stew red cabbage in water and pour off the water for use as an indicator solution. Methyl orange is one of the indicators commonly used in titrations. In an alkaline solution, methyl orange is yellow and the structure is: Now, you might think that when you add an acid, the hydrogen ion would be picked up by the negatively charged oxygen. I assume this refers to a pH indicator, such as indicator paper that you dip into a solution. This tells you the pH of the solution, i.e. whether it is an acid, a base, or neutral. Methyl orange Methyl orange is one of the indicators commonly used in titrations. In an alkaline solution, methyl orange is yellow and the structure is: Now, you might think that when you add an acid, the hydrogen ion would be picked up by the negatively charged oxygen. That's the obvious place for it to go. The purpose of the Myers-Briggs Type Indicator® (MBTI ®) personality inventory is to make the theory of psychological types described by C. G. Jung understandable and useful in people's lives. An indicator may be needed. Often a titration is repeated until successive titres are within 0.1 cm 3. An indicator is a substance that undergoes a change in colour when the end-point of a titration is reached. Acid-base indicators are used to signal the end of acid-base titrations.
http://www.avogadro.co.uk/chemeqm/acidbase/titration/phcurves.htm http://antoine.frostburg.edu/chem/senese/101/acidbase/faq/universal-indicator.shtml http://chemguide.co.uk/physical/acidbaseeqia/indicators.html http://www.answers.com/Q/What_is_the_purpose_of_an_indicator_in_chemistry http://chemguide.co.uk/physical/acidbaseeqia/indicators.html http://www.myersbriggs.org/my-mbti-personality-type/mbti-basics/ http://www.avogadro.co.uk/chemeqm/acidbase/titration/phcurves.htm
what is the purpose of the indicator