My teacher asked me to write a theory and discussion about an acid base titration. The procedure is: pipette 10 ml of NaOH solution (0.152 N) and transfer it to a cynical flask, add 2 drops of methyl red indicator (yellow colors). I used 15.2 ml of HCl and the solution color changed to purple.

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Acid-base titration is a chemical method to determine the concentration of either the acid or the base. It is based on the fact that acid and base neutralize each other completely. This reaction measures the amount of acid or base required to fully neutralize the other, in the presence of a color change indicator, and uses it to measure the concentration of the unknown species (acid or base).

In the given case, 10 ml of sodium hydroxide solution (NaOH) that has a concentration of 0.152 N is titrated with 15.2 ml of HCl, in the presence of methyl red. The indicator will change the solution color from yellow to red when the titration is complete. 

Using the equation: C1V1 = C2V2

where, C1 and C2 are the concentration of acid and base, and V1 and V2 are the volumes of acid and base used, respectively; we can calculate the concentration of the acid as:

15.2 x C1 = 0.152 x 10 

solving the equation, we get the concentration of HCl as 0.1 N.

Thus, the method can be used to determine the concentration of acid or base, given the volumes needed to titrate them and the concentration of the other species. 


Hope this helps.

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