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

The aim of the experiment is to find the relative formula mass of an unknown acid in an acid solution that I was provided.

Extracts from this document...

Introduction

Table of contents 1.1 Aim of the experiment 2 1.2 Introduction 2 1.3 Equipments and apparatus 2 1.4 Safety precautions 2 2.1 Procedure 3 2.2 Apparatus setup 3 2.3 Analysis 4 3.1 Implementing 5 3.2 Analyzing 6 4.1 Evaluation 8 4.2 Comparison between experimental Mr with value 8 of likeliest acid 4.3 Conclusion 8 THE RELATIVE FORMULA MASS OF AN UNKNOWN ACID 1.1 Aim of the experiment The aim of the experiment is to find the relative formula mass of an unknown acid in an acid solution that I was provided. 1.2 Introduction I was provided with a solution of a monobasic (monoprotic) acid. Monoprotic acid is an acid that contains only one hydrogen atom. I was to determine the molarity of the acid by titration with a sodium hydroxide solution, and then use this molarity to calculate the relative formula mass of the acid. An acid is a substance that releases hydrogen ions when dissolved in water. There are two types of acids called organic acids and mineral acids. Organic acids, such as methanoic acid, citric acid or latic acid, are obtained from plant and animal sources. From the other side, mineral acids (hydrochloric acid, nitric acid or sulphuric acid) are made from minerals. ...read more.

Middle

3. Compare your calculated Mr value with the Mr value of likeliest acid. Calculate the percentage difference between these two values. 3.1 Implementing 1. Wash all the equipments used in the experiment (including burette, conical flask, pipette, pipette filler and beaker) with distilled water in the wash bottle. 2. Use pipette to transfer 25 cm3 of sodium hydroxide (alkali) solution into a conical flask. 3. Add 3 or 4 drops of phenol red indicator to the conical flask into which NaOH solution was put. 4. Fill the burette by pipette filler with acid solution up to point 0.00. 5. Take the point at which level of acid solution is least as the initial reading. Wash the side of conical flask during the titration. 6. Swirl the solution in the conical flask for the indicator to disperse evenly and continue swirling while adding the acid solution from the burette as well. 7. Start adding acid solution drop wise from the burette carefully to be able to stop adding acid solution at a correct point when the endpoint is reached. 8. When the purple colour starts to change to yellow, stop adding acid solution. This is the endpoint. 9. Read correctly the final reading of volume on the burette when the endpoint is reached. ...read more.

Conclusion

/ 250 = � 0.2% 3. The percentage maximum error in use of burette Burette � 0.15 cm3 (maximum error) % error = (0.15 � 100) / 28 = � 0.5% 4. The overall apparatus error The overall apparatus error = 0.2% + 0.2% + 0.5% = � 0.9% 4.2 Comparison between experimental Mr with value of likeliest acid My experimental value is 62.37 which are theoretically very close to the value of nitric acid from the table (shown in analysis part) whose value is 63. If I add the percentage of error to my experimental result, I will get the value of 63.27. Final experimental result = experimental value + the overall apparatus error = 62.37 + 0.9 = 63.27 % difference between experimental Mr and value of likeliest value = (62 / 63.27) � 100% = 100% - 97.99% = 2.01% 4.3 Conclusion From the titration process I found the molarity of the sodium hydroxide solution and the relative formula mass of the unknown acid. With further calculations I identified the correct formula of the acid. The experiment was done without any major mistakes and complications, although there were some minor mistakes in calculations due to the apparatus used. This could be solved in another experiment by using more appropriate equipments. It will reduce the overall percentage error and minimize the mistake. ?? ?? ?? ?? The relative formula mass of an unknown acid Mateja Dujmovic Ankara, Turkey 1 ...read more.

The above preview is unformatted text

This student written piece of work is one of many that can be found in our GCSE Aqueous 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 GCSE Aqueous Chemistry essays

  1. Determine the relative formula mass and the molecular formula of succinic acid

    So the mass of the acid solution required to neutralize the standard alkali solution will be .00125*132=0.165g. Hence, the titration volume of solution will be 250/1.65*.165=25cm3 Similarly, if n=1 Mr of succinic acid will be 104. So the mass of the acid solution required to neutralize the standard alkali solution will be .00125*104=0.13g.

  2. Antacid Experiment.

    I was correct but through this final graph we will see how close my prediction was. This graph shows that my predictions were accurate. The purple bar is the average titration and the maroon coloured bar is my predictions. By looking at them you can see that I was accurate apart from the prediction for boots.

  1. Identification of an Organic Unknown.

    Test for carbonyl group Apparatus: * Pipette * Measuring cylinder * Test tube * 2,4 Dinitrophenylhydrazine solution * Water bath Procedure: To 1cm3 of 2,4 dinitrophenylhydrazine add several drops of the unknown substance using a pipette. Heat with a water bath if necessary.

  2. Titrating Sodium hydroxide with an unknown molarity, against hydrochloric acid to find its' molarity.

    be stable in air at ordinary temperatures * It must be easily soluble in water * It must have a high molar mass * It must be in solution when used in volumetric analysis , must undergo complete and rapid reaction The concentration of the sulphuric acid is said to be between 0.15moldm-3 and 0.05moldm-3.

  1. In order to find out the exact concentration of sulphuric acid, I will have ...

    Percentage error = Sodium carbonate percentage error = Volumetric flask percentage error = Volume of distilled water percentage error = Average titre percentage error = Pipette percentage error = Now that I have worked out each margin error, I should be able to add all previous values to achieve a percentage total.

  2. Finding out how much acid there is in a solution.

    In this experiment I will make sure that I wear a lab-coat and goggles at all times as I am working with harmful chemicals and glassware. I will make sure that I am very careful in handling the equipment and chemicals and avoid spillages, and coming in contact with the chemicals being used.

  1. Identification of an unknown organic compound

    Apparatus needed: * Water * Unknown organic compound * Sodium hydrogen carbonate * Test tube * Limewater E.g CH3COOH + NaHCO3 --> CH3COONA 2 + CO2 +H2O Esters Esters can be formed from the reaction of carboxylic acid and alcohol in the presence of an acid catalyst and heat to give an ester and water.

  2. Precipitation of Salts & Identification of Unknown Solutions

    However, according to the solubility rules, seventeen of these twenty four combinations were meant to produce precipitates. All salts containing chloride anions are soluble in an aqueous solution with the exception of Ag+, Hg+ and Pb2+.

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