late nite lab what color does the indicator change to during the course of the titration?

by Otilia Denesik 5 min read

What color does the indicator change to during the titration?

Mar 11, 2021 · Question Correct What color does the indicator change to during the course of the titration? 4 1.00 points out of 1.00 Select one: ... Course Hero member to access this document. Continue to access. ... Titration Tutorial Late Nite Labs. lab. 3. chem-quiz.docx. No School. AA 1. pH of the HCl solution; No School • AA 1.

How many ml of HCL were used in the fine titration?

Oct 19, 2020 · Hence, the end point is indicated by change in color from colorless (ph less than 7) to faint pink (ph = 7.5) Thus Phenolphthalein is correct answer. Thanks 3. How many mL of 0.100 M sodium hydroxide were added to the burette before …

Why was indicator added to Erlenmeyer flask with unknown HCl solution?

May 02, 2019 · How will you determine the color change? You will expect it to be a purple color, as that is what is is when pH> 7. When the HCl is greater than the equivalence point, the solution will turn transparent. 3. Suppose you titrated a sample of acetic acid (monoprotic acid) with a 0.125 M solution of NaOH.

What is the difference between fine titration and coarse titration?

The indicator is phenolphthalein , it is colourless in acidic solutions and light pink in basic solutions . B) How do you explain the fact that potassium hydrogen phthalate (KHP) is an acidic substance? It is acidic because it has a pH of 5.4 and according to the pH scale any value lower than 7 is acidic.

What color does the indicator change to during the course of the titration?

The end point of a titration is the point at which the indicator changes color. When phenolphthalein is the indicator, the end point will be signified by a faint pink color.

How do you explain the color change of solution at the end point of titration?

The acid–base indicator indicates the endpoint of the titration by changing color. The endpoint and the equivalence point are not exactly the same because the equivalence point is determined by the stoichiometry of the reaction while the endpoint is just the color change from the indicator.

What happens if you change the indicator in a titration?

When you reach the endpoint of your titration, the indicator changes color. This happens because any unreacted molecules in excess of those needed to reach the endpoint reacts with the indicator molecules. This changes the structure of the indicator molecule so that its color changes.Apr 24, 2017

What happened to the color of the indicator once the equivalence point was reached?

(Lab 10) How many mL of HCl were added to the flask? (Lab 10) What happened to the color of the indicator once the equivalence point was reached? It turned pink.

Why does color change at the endpoint?

A few drops of the indicator are added to the flask before you begin the titration. The endpoint is the point where the indicator changes color, which tells us that the acid is neutralized by the base. The equivalence point is the point where the number of moles of acid exactly equals the number of moles of base.Feb 23, 2012

What happens to the color of the indicator?

When universal indicator is added to a solution, the color change can indicate the approximate pH of the solution. Acids cause universal indicator solution to change from green toward red. Bases cause universal indicator to change from green toward purple.

What color is thymol blue in bleach?

brownish-greenThymol blue (thymolsulfonephthalein) is a brownish-green or reddish-brown crystalline powder that is used as a pH indicator.

What does Bromothymol blue indicate?

Bromthymol Blue is a dye used as an indicator in determining pH. Bromthymol blue is a weak acid. It can be in acid or base form, depending on the pH of the solution. This reagent is yellow in acidic solutions, blue in basic solutions and green in neutral solution.

Does phenolphthalein turn pink?

Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and pink in basic solutions.

Why does pH change rapidly at equivalence point?

Near the equivalence point, a change of a factor of 10 occurs very quickly, which is why the graph is extremely steep at this point. As the hydronium ion concentration becomes very low, it will again take a lot of base to increase the hydroxide ion concentration by 10 fold to change the pH significantly.

Why is the equivalence point higher than 7?

Because the conjugate base of a weak acid is weakly basic, the equivalence point of the titration reaches a pH above 7. Conversely, for the titration of a weak base with strong acid, the pH at the equivalence point is less than 7 because only the conjugate acid is present.Sep 21, 2019

How do you find ka?

Find the dissociation constant with the formula Ka = [H+]²/([HA] – [H+]), where Ka is the dissociation constant, and [HA] is the concentration of the acid before dissociation. ... The Ka expression is Ka = [H3O+][C2H3O2-] / [HC2H3O2]. ... 1) The acid dissociation constant (Ka) for benzoic acid is 6.3 x 10-5.More items...•Nov 27, 2021