On 310 of the destroyer, it states that an indicator is red in undiasociated form and yellow in dissociates form. At a low pH, the color is red (since you assume the indicator to be weak acid or base, in this case HIn --> H+ + In-.) Adding acid makes it shift left to undiasociated form. But if we used a weak base as indicator such as NH3, wouldn't it be NH3 + H2O --> NH4+ + OH- ? then adding H+ would make it shift right to undiasociated form right? (Since H+ makes OH- cxn go down).
Question on color of indicator (if unknown what indicator is) in acidic solution.
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You seem to be approaching this in a very incorrect manner. This is an easy problem.....Don't overthink it.
Let HA be the undissociated form.....Let A- be the dissociated form......at a low pH there is a huge amount of H+ ions....correct ?
Clearly this means the HA form predominates,,,,,thus the color is red !!!!
Problem 245 is the more challenging one🙂 !!!
Hope this helps......
Dr. Romano
Sorry. I saw in the answer it said that you can use a weak acid or a weak base as a buffer. So I was wondering what would happen if a weak base was used as a buffer instead? Just for curiosity's sake
http://www.chemcollective.org/activities/tutorials/buffers/buffers3 Is this example at the bottom correct? I think it gets the same answer as using a weak acid as a buffer. It just looks a bit harder. I'll just stick with what you told me. But is this example right?
