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Methyl red in titration (1 Viewer)

js992

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For a titration with a strong acid and strong base, the equivalence point will be about a pH of 7 and bromothymol blue is the optimal indicator.

My question is, how suitable is methyl red as an indicator for a strong acid strong base titration?

My school's bromothymol blue went off and our teacher told us that it was fine just to use methyl red. He said the pH curve was so steep that the end point marked by methyl red is roughly around the equivalent point.

This doesnt sound right to me... roughly how off would the results be?
 

pwoh

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From Jacaranda Chemistry 2:
[Strong acid - strong base titration]

The equivalence point is at the centre of
the inflection (pH = 7). All three indicators change colour
within this steep portion of the pH curve. Although the
bromothymol blue end-point most closely matches the pH at
the equivalence point
, we can use any of these three indica-
tors for the titration, as their end-points are all within this
steep portion of the pH curve. The accuracy of the technique
is not sufficiently great to notice any difference in end point
for the three indicators.
 

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