Hi Cna someone please tell me what I must out into the Trial 1 column? It would be greatly appreciated.
theLab: Determining the Ksp For Ca(OH)2
Purpose: The purpose of this experiment is to determine the Ksp for calcium hydroxide.
Experimental Design: A saturated solution of calcium hydroxide is titrated with a hydrochloric acid solution of known concentration to a bromophenol blue endpoint (yellow).
Materials:
50.0 mL of 0.10 M HCl(aq)
bromophenol blue indicator
50.0 mLsaturated calcium hydroxide
50.0 mL buret
125 mL Erlenmeyer flask
50.0 mL of distilled water
10 mL pipet with pump
waste beaker
Procedure:
1.Fill the buret with the acid solution.
2.Pipet 10.0 mL of calcium hydroxide into the flask.
3.Add approximately 10.0 mL of water to the flask.
4.Add 4 drops of bromophenol blue to the flask.
5.Titrate the base to an endpoint and record the volume of acid added.
6.Dispose of the flask contents into a waste beaker.
7.Repeat steps 2-6 four more times.
Analysis:
1.Present your data in a table. Use the following table as a guide:
Trial 1 Trial 2
Initial volume of HCl(mL)
Final volume of HCl(mL)
Volume of HCl added(mL)
125 mL Erlenmeyer flask
50.0 mL of distilled water
10 mL pipet with pump
waste beaker
Procedure:
1.Fill the buret with the acid solution.
2.Pipet 10.0 mL of calcium hydroxide into the flask.
3.Add approximately 10.0 mL of water to the flask.
4.Add 4 drops of bromophenol blue to the flask.
5.Titrate the base to an endpoint and record the volume of acid added.
6.Dispose of the flask contents into a waste beaker.
7.Repeat steps 2-6 four more times.
Analysis:
1.Present your data in a table. Use the following table as a guide:
Trial 1 Trial 2
Initial volume of HCl(mL)
Final volume of HCl(mL)
Volume of HCl added(mL)
If you have all of the information posted, then 500 mL of the saturated solution of Ca(OH)2 must have used 0.10 x 0.050 L = 0.005 mols HCl. The reaction is
Ca(OH)2 + 2HCl ==> CaCl2 + 2H2O.
Therefore, mols Ca(OH)2 must be 1/2 of the HCl mols or 0.005/2 = 0.0025.
From there you can calculate (Ca^+2) and (OH^-) and Ksp. Post your work if you get stuck or if I have misinterpreted the problem. Can it be chance that you used EXACTLY 50.0 mL HCl or is that what you started with?
Let me repost the important information only:
Purpose: The purpose of this experiment is to determine the Ksp for calcium hydroxide.
Materials are:
*50.0 mL of 0.10 M HCl(aq)
*bromophenol blue indicator
*50.0 mLsaturated calcium hydroxide
*50.0 mL buret
*125 mL Erlynmyer Flask
*50.0 mL of distilled water
*10.0 mL pipet with pump
*waste beaker
The procedure for the lab is:
1.Fill the buret with the acid solution.
2.Pipet 10.0 mL of calcium hydroxide into the flask.
3.Add approximately 10.0 mL of water to the flask.
4.Add 4 drops of bromophenol blue to the flask.
5.Titrate the base to an endpoint and record the volume of acid added.
6.Dispose of the flask contents into a waste beaker.
7.Repeat steps 2-6 four more times.
The following is what I am having trouble with.
Present your data in a table.Use the following table as a guide:
Trial 1 Trial 2 Trial 3
*Initial volume
of HCL(mL)
*Final volume
of HCL (mL)
*Volume of
HCL added (mL)
I am having difficulty regarding the trial 1 column. What is my initial volume of HCL(mL) supposed to be?
The table doesnt want to be neat but the trial 1, trial 2 and trial 3 should be shifted more to the right side
The initial volume of HCl is the reading of the buret at the beginning of the titration. It may or may not be zero. Then you have a final volume HCl. The volume of HCl added, then, is the difference between the two columns; i.e., the final volume reading minus the initial volume reading. For example, you may have started with a buret reading of 0.75 mL. That will be the initial volume of HCl. Then suppose you titrated with HCl and the indicator changed at 24.55 mL. That will be the final volume. Then the volume HCl used will be
24.55 - 0.75 = 23.80 mL.
Here are my results:
*Initial volume
of HCL(mL)
Trial 1- 0.0
Trial 2- 2.51
Trial 3- 4.95
Trial 4- 7.4
Trial 5- 9.9
*Final volume
of HCL (mL)
Trial 1- 2.51
Trial 2- 4.95
Trial 3- 7.4
Trial 4- 9.9
Trial 5- ?
*Volume of
HCL added (mL)
Trial 1- 2.51
Trial 2- 2.44
Trial 3- 2.45
Trial 4- 2.50
Trial 5- ?
How would I get Final volume of HC (mL) and Volume of HCL added (mL) for trial 5?
To fill in the "Trial 1" column in the table, you need to follow the procedure provided and record the appropriate data for each trial. In this experiment, you are titrating a saturated solution of calcium hydroxide with a hydrochloric acid solution of known concentration.
Here's a step-by-step guide to obtain the data for the "Trial 1" column:
1. Fill the buret with the hydrochloric acid solution.
2. Pipet 10.0 mL of the saturated calcium hydroxide solution into the Erlenmeyer flask.
3. Add approximately 10.0 mL of water to the flask.
4. Add 4 drops of bromophenol blue indicator to the flask.
5. Slowly add the hydrochloric acid from the buret to the flask while swirling the flask gently. Continue until there is a noticeable color change in the solution from blue to yellow. This is the endpoint.
6. Record the initial volume of hydrochloric acid solution in the buret. This is the volume before you start adding it to the flask.
7. Record the final volume of hydrochloric acid solution in the buret. This is the volume after you have reached the endpoint.
8. Calculate the volume of hydrochloric acid added by subtracting the initial volume from the final volume.
9. Dispose of the contents of the flask into a waste beaker.
10. Repeat steps 2-9 four more times for a total of five trials.
In the "Trial 1" column, you would record the values obtained for the initial volume of HCl, final volume of HCl, and volume of HCl added for the first trial.
After completing all five trials, you can continue to fill in the "Trial 2" column in the same manner.