• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

To draw and explain the shape of graphs of pH against volume of titrant for titrations involving monoprotic acids and bases.

Extracts from this document...

Introduction

Problem: To draw and explain the shape of graphs of pH against volume of titrant for titrations involving monoprotic acids and bases. The combinations we had were: 1) strong acid + strong base (titrant), 2) weak acid + strong base (titrant) and 3) weak base + strong acid (titrant). Data collection: Procedure: We had the different acids and bases in the beaker respectively in the burette and dropped the titrant into the beaker where we had a pH-meter and recorded the result. 1) We had HCl in a 20 ml beaker and NaOH in a 50 ml burette and a few drops of BTB. 2) We had HAc in a 20 ml beaker and NaOH in a 50 ml burette and a few drops of BTB. ...read more.

Middle

5,2 18 5,3 19 5,6 19,5 5,9 20 6,3 20,3 6,8 20,7 10,4 21,1 10,6 21,5 11,0 22 11,1 23 11,4 24 11,55 26 11,75 28 11,9 30 12,0 32 12,1 ml ph 0 1,2 5 1,2 6 1,3 9 1,3 10 1,4 11 1,45 13 1,5 15 1,65 16 1,7 17 1,75 19 1,9 19,5 2,0 20,5 2,2 21 2,2 23 2,35 24 2,7 24,2 4,6 24,5 5,1 24,8 6,0 25 7,1 25,5 7,3 26 7,6 27 7,8 28 8,1 30 8,2 32 8,4 34 8,3 36 8,8 38 8,9 Data processing and presentation: All the results were very much similar - producing very similar graphs. Of course there are uncertainties present. For example it is easy to put in a few drops too much from the burette and the thing is not so accurate any more. ...read more.

Conclusion

There were many interesting steps to go through etc. Looking at the tree different graphs we got from our three attempts, they are all very similar. This leads me to the conclusion that they are correct. As we have no literate value to compare it with I can interpret it as that we got where we wanted. Of course the process can always be better and improved. But I think the method we used here is rather accurate, accept for the uncertainties due to bad measurements. The use of BTB as an indicator makes it very clear to see when the solution is acid respectively basic, which is an advantage. On the other hand, the intervals we dripped the titrant into the other liquid were not even which does not give a good result. It can always be improved. ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our AS and A Level Physical Chemistry section.

Found what you're looking for?

  • Start learning 29% faster today
  • 150,000+ documents available
  • Just £6.99 a month

Not the one? Search for your essay title...
  • Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month

See related essaysSee related essays

Related AS and A Level Physical Chemistry essays

  1. Acid-Base Titrations.

    For example, we might prepare a 0.1000 molar solution of primary standard oxalic acid by weighing out exactly 0.1 moles of oxalic acid and diluting to one litre in a volumetric flask.

  2. Identification of amino acids by chromatography.

    If I was repeating this investigation, I would like more time, which I think would improve the accuracy of the results. ? I would leave the albumen/trypsin solution in for 28 hours in a sterile environment to ensure that the protein had been fully broken down into the amino acids and that there had been no contamination.

  1. Antacid Lab. Are name brand antacids better than generic brand antacids to neutralize ...

    The group decided to speed up the process, as we saw that the drops were not affecting antacids too much, we measured 60 drops to be equal to one pipette of solution. This resulted in us adding one pipette of stomach acid to each antacid considering it as 60 drops of stomach acid.

  2. Investigating the Rate of the Reaction between Bromide and Bromate Ions in Acid Solution

    Next, the results when I varied the concentration of bromate ions: [BrO3-] /mol dm-3 Repeat 1 Repeat 2 Repeat 3 Repeat 4 Repeat 5 Time/s Temp/K Time/s Temp/K Time/s Temp/K Time/s Temp/K Time/s Temp/K 1.25x10-3 132 295.5 130 296

  1. Obtaining pH curves for acid/alkali titrations.

    Or: pH = -Log10 Ka Prediction I know that the curve for a weak acid/strong alkali should start higher up the axis than a strong acid/strong base curve. This results in the vertical section of the graph being shorter and due to salt hydrolysis, the curve will rise to 14 far quicker than it should.

  2. Free essay

    Experiment. Is the order of reaction affected if the acid is monoprotic or diprotic?

    until the reaction stops. This method is the most efficient method and it will enable me to get many readings and thus allow me to process my data into graphs in order to help me workout the orders of my reactions.

  1. Investigating the Volume of a Drop

    Nestle Pure Life natural spring water (bottled water) 4 Styrofoam cups 1 Procedures: 1. Prepare a data table with columns named "Start volume", "End Volume", "Difference" and "Volume per drop". Example: Start volume End Volume Difference Volume per drop 2. Put bottled water two Styrofoam cups. Take one of the cups and add table salt in it.

  2. Acids and Bases in the World - acid rain, chlorine in pools and cleaning ...

    This term is also described as saphonification 3. The process by which produces soap, it involves base hydrolysis of triglyceride?s, which are esters (chemical compounds derived by an oxoacid reacting with a hydroxyl compound e.g. alcohol) of fatty acids to form the salt of a carboxylate 4. The hydroxide ion adds to the carbonyl (a compound containing metal combined with carbon monoxide ? e.g.

  • Over 160,000 pieces
    of student written work
  • Annotated by
    experienced teachers
  • Ideas and feedback to
    improve your own work