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pinky2468
Nov29-04, 07:22 AM
I am very stuck on this question and I am hoping someone can help me with this. We did this in lab and mine did not come out right, but I still have to turn it in and my lab teacher said to figure it out!
Buffer solutions using a cabbage dye indicator:
Which of these is a buffered solution after the addition of 5 drops of HCl, 10 drops HCl:
distilled water (I think no?)
0.1 M NaCl
pH 12 buffer
pH 2 buffer

Which if these is a buffered solution after 5 drops NaOH, 10 drops NaOH:
juice(pH around 4.5)
soda(pH around 3)
pH 12 buffer
pH 2 buffer

I know this is a loaded question, but I can't figure out which ones...HELP!!!

Monique
Nov29-04, 09:51 AM
Hi pinky, a buffer is a solution that contains a mixture of acids and bases.. if an acid or base is added to the solution the pH won't change. If you add a solution to a buffer outside it's buffering range, the buffer will loose it's power.

So thinking of that, which do you think the correct answer will be to your own question? Hint: what is the approximate pH of HCl and NaOH?

pinky2468
Nov29-04, 03:27 PM
HCl is a pH 2 and NaOH is about pH-13-14 right? So, pH 2 is a buffer solution when HCl is added and not when NaOH is right? The rest I am still lost on!?