CHEM 1101 Study Guide - Final Guide: Volumetric Flask, Sodium Hydroxide, Titration

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These sheets cannot be taken into the lab exam. Acid-base titration: the lab exam is 75 min, do not discuss with other students this will result in removal of exam sheet. Show all the calculations on the exam sheet. Almost 50% of your marks are for the calculations: you are allowed to use your lab notebook (no other extra sheets), given (1. 000 0. 005) m stock solution of hcl. Pour approximately 25ml of the 1. 000m solution provided to you into a 50ml beaker. Pipet from the beaker 10. 00 0. 02 ml of this into a 100. 00 0. 08 ml volumetric flask and fill up to the line with distilled water: diluted hcl stock solution calculation: Using m1 v1 = m2 v2 and rearranging the formula to solve for m2 . V1 is volume of hcl which is 10 ml. M2 is the molarity of hcl that you are making up. V2 is the final volume of diluted hcl (100 ml )

Related Questions

heat of solution:

I will have this experiment on next lab and want to be preparedfor it but don't know how to calculate

some things like molarity, initial and final temperature, changein temperature, heat of neutralization per mole and so on :(( .. Iwill be grateful for explaining to me how to solve each problemstep by step, so will be able to do it on my own later. Thankyou!!!!

page 60: and without piecing the bottom, record the temperatureof the HCL solution. Rinse the termometer and then record thetemperature of the NaOH solution in the Erlenmeyer glask. The twotemperatures must be within 2C before starting the experiment.Record the temperatures and take the acerage as the initialtemperature. Using a clean 50ml graduated cylinder, pour 25ml ofNaOH solution into the Styrofoam cup calorimeter... so on soon.....Record the the maximum temperature that was observed asfinal temperature. Determine the change in temperature,(triangle)T. Assuming that the density of the solution was 1,00g/ml and the final colume of the solution was 50,0ml, determine themass of the solution. Given that the specific heat of water is 4.18J/g C, calculate the (triangle)H for theneutralization reaction.Finally calculate the (triangle)T for the neutralization reactionper mole for H⁺ and OH^- ions reacting.

Repeat the procedure for trail 2 and after trial 2 calculate theaverage (triangle)H for the neutralization reaction per mole ofH⁺ and OH^- ions reacting.

1-How many grams of NaCl would be needed to prepare 150.00 L of a 1.402 M NaCl solution?

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2- first a standardized solution of sodium hydroxide (NaOH) will be quantitatively diluted to about 0.1 M but not exactly 0.1M. The molarity of the dilute NaOH will be calculated! A similar quantitative dilution was done in experiment 3 when you diluted 5.0 M HCl to 0.50M HCl using a volumetric flask and pipet.

The second part of the experiment is very similar to the last part of experiment 6 where samples of the unknown were weighed out, dissolved in water, and titrated with the dilute NaOH using phenolphthalein as the indicator to determine the percent by mass of a compound in the unknown. The compound will be different than the compound used in experiment 6. The molecular formula of the compound will be provided during the final. You must know how to weigh by difference (Preweigh, tare sample and small container to zero, transfer sample to flask, and place the small container back on balance to get mass) and titrate the sample using the buret in order to do well.

Be sure to read the instructions for the practical toward the end the CHM151L lab manual and do the practice problem on the next page.

You will have 1.5 hours to do the practical. You may only use a calculator and a pencil on the practical. There is no talking during the practical such that students cannot help each other and the TA may only help you with equipment problems.

It would be a good idea to wash any glassware you might use the lab period before the lab practical. There will also be a help session before the lab practical.

At the end of the lab final you will wash all glassware used or any dirty glassware in your locker, wash your unknown vials and remove the labels, checkin your locker and return your key, and evaluate the lab.

Please put the following statements in the correct order relating to the day of the lab practical:
1 2 3 4 5 6 Wash all your glassware and unknown vials, checkin your locker, evaluate the lab, and check your grades.
1 2 3 4 5 6 Do at least 3 good trials (weigh and titrate sample) as time allows.
1 2 3 4 5 6 Start the lab practical by diluting the NaOH solution.
1 2 3 4 5 6 Before the day of the practical clean glassware, read the practical instructions and do the practice problem in the lab manual and complete the loncapa problems for the final.
1 2 3 4 5 6 Calculate the molarity of the dilute NaOH, the percent by mass of the compound in you unknown for each trial and then the median.
1 2 3 4 5 6 Come to the help session before the lab final.

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A NaOH solution was prepared by diluting 5.00 mL of 2.205 M NaOH to a final total volume of 100.00 mL. What is the exact molarity of the dilute NaOH (use 4-5 significant figures)?

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4-For the problem above, select glassware and size from the list below to conduct the dilution.

A	Amber Bottle
B	Mohr pipet
C	Buret
D	Volumetric Flask
E	Volumetric Pipet or Pipettor
F	Graduated cylinder
G	Erlenmeyer flask
H	Beaker

A B C D E F G H <= Glassware used to transfer the 2.205 M NaOH to be diluted
A B C D E F G H <= Glassware used to measure the final volume of the diluted M NaOH.

5 10 15 20 25 50 100 250 500 1000 <= Volume of the glassware chosen to transfer the concentrated NaOH above
5 10 15 20 25 50 100 250 500 1000 <= Volume of the glassware chosen to contain the final dilute NaOH above.

Direction:

Part I - Prepare and standardize a solution of Sodium Thiosulfate 1. Prepare 250 mL of a solution which is approximately 0.025 M Na2S2O3â¢ 5H20. Because sodium thiosulfate is a hydrate, it cannot be used as a primary standard. It must be standardized in order to determine its exact concentration. (Note for Suâ17: this solution has already been prepared for you). 2. Pipet 10.0 mL of 0.01 M KIO3 into a 150 mL Erlenmeyer flask. Add about 20 mL of distilled water to the flask. 3. Dissolve about 2 g of solid KI to the KIO3. The solution should turn a dark orange-brown. Add about 20 drops of 2M HCl and swirl to mix completely. 4. Calculate the approximate amount of Na2S2O3 that will be required to reach the endpoint, assuming that the Molarity of the Na2S2O3 will be approximately 0.025 M. 5. Quickly add all but about 2 or 3 mL of the volume you calculated above to the flask. 6. Add about 40 drops of a 2% starch solution. The solution should turn dark blue. 7. Continue adding Na2S2O3 dropwise until the blue color just disappears. Record the volume of Na2S2O3 in your lab notebook. 8. Repeat one more time. Calculate the concentration of the Na2S2O3 from each trial and average your results. If they differ greatly, a third trial may be necessary. Part II - Prepare a saturated solution of Ca(IO3)2 1. Combine 100.0 mL of 0.20 M KIO3 with 40 mL of 1M Ca(NO3)2 in a 150-mL beaker. Stir to mix the solutions completely. A white precipitate of Ca(IO3)2 should form. 2. Let the mixture stand a few minutes, then filter into a dry flask, through a dry filter paper using gravity filtration. Cover the solution with parafilm.

Show me part2 how to calculate the concentration of iodate ion in the filtrate. Using the equation editor, insert---> eqatuion.

CHEM 1101 Study Guide - Final Guide: Volumetric Flask, Sodium Hydroxide, Titration

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