Table of Contents
Which indicator is suitable for titration of HCl and NaOH?
A suitable indicator for the titration of the weak acid CH3COOH(aq) and the strong base NaOH(aq) would be either thymol blue (pH range 8.0 – 9.6) or phenolphthalein (pH range 8.3 – 10.0).
What happens when you titrate NaOH with HCl?
During the course of the titration, the titrant (NaOH) is added slowly to the unknown solution. Up to the equivalence point, the solution will be acidic because excess HCl remains in the flask. After the equivalence point, there will be an excess of NaOH and the solution will be basic.
Why the volume of HCl at using Mo is less than using pH pH?
and the pH increases to 1.30. At the equivalence point the moles of HCl and the moles of NaOH are equal. Since neither the acid nor the base is in excess, the pH is determined by the dissociation of water. Titration curve for the titration of 50.0 mL of 0.100 M HCl with 0.200 M NaOH.
Why universal indicator is not suitable for titration?
The universal indicator is not used in titration because they have different pH ranges. It becomes difficult to determine the exact pH of the solution. Therefore, universal indicator is not used in titration.
What happens if you use the wrong indicator in a titration?
In contrast, using the wrong indicator for a titration of a weak acid or a weak base can result in relatively large errors, as illustrated in Figure 17.3. 3.
Why phenolphthalein is not used in HCl titration?
In the same way in the Titration of weak base versus strong acid there is a sudden change in the pH of 3.5 to 8.0,near the neutralisation point. So Phenolphthalein can’t be used since its pH range is 8.3 to 10.0.
Why is phenolphthalein used for HCl and Naoh?
A strong acid- strong base titration is performed using a phenolphthalein indicator. Phenolphtalein is chosen because it changes color in a pH range between 8.3 – 10. It will appear pink in basic solutions and clear in acidic solutions.
Why NaOH is used in titration?
Sodium hydroxide is used in titration if the unknown sample solution is acidic because bases are used to neutralize acids.
What is the approximate pH of hydrochloric acid?
3.01
pH of Common Acids and Bases
| Acid | Name | 1 mM |
|---|---|---|
| H2SO4 | sulfuric acid | 2.75 |
| HI | hydroiodic acid | 3.01 |
| HBr | hydrobromic acid | 3.01 |
| HCl | hydrochloric acid | 3.01 |
Which indicator is not used for weak base and strong acid titration?
Choice of Indicators
| Types of titration | Indicators |
|---|---|
| Strong acid-weak base | Methyl orange will change sharply at the equivalence point. |
| Weak acid-weak base | Neither phenolphthalein, not methyl orange is suitable. No indicator is suitable because it requires a vertical portion of the curve over two pH units. |
Why are different indicators used in titration?
Titrations. Because a noticeable pH change occurs near the equivalence point of acid-base titrations, an indicator can be used to signal the end of a titration. When selecting an indicator for acid-base titrations, choose an indicator whose pH range falls within the pH change of the reaction.
What happens when you titrate HCl and NaOH?
HCl is a strong acid and NaOH is a strong base. Therefore, titrating one against the other yields a complete reaction. The titration is complete when the pH reaches 7.0. Methyl orange would not be appropriate here, as the color change occurs at between 3.1 and 4.4 in an aqueous solution.
What is the pH at the end of phenolphthalein titration?
When the titration is carried out , HCl is aded until the solution turns colorless. This is the phenolphthalein end point of the titration . The pH will be ≈8.3. This is the pH of a NaHCO3 solution in water.
What is the titration curve when HCL is present in flask?
In all beakers, aqueous HCl acid solution is present and aqueous NaOH solution is added to HCl solution. At the beginning (no addition of NaOH) pH is depends on the concentration of NaOH and when concentration of HCl decreases pH value increases. So we are done with titration curve when HCl is in the flask.
What happens to the pH curve when HCL is added to NaOH?
At the beginning (no addition of NaOH) pH is depends on the concentration of NaOH and when concentration of HCl decreases pH value increases. So we are done with titration curve when HCl is in the flask. Now we are going to focus on how pH curve will vary when flask holds NaOH and adding HCl.