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

Determination of the relative atomic mass of Lithium using Titration.

Extracts from this document...

Introduction

Experiment (Titration) Determination of the relative atomic mass of Lithium Aim: To determine the relative atomic mass of Lithium Introduction: In this investigation I will determine the relative atomic mass of Lithium by two different methods. * First I will measure the volume of Hydrogen gas * Secondly by titrating the Lithium Hydroxide produced Apparatus * Safety Spectacle * Filter funnel * Burette, 50 cm3 * Clamp stand * Pipette one 25cm3 * Teat pipette * 2 Conical flask 25 cm3 * Beakers * 25cm3 Measuring Cylinder * Phenolphthalein indicator solution * Hydrochloric acid solution * Stopper * Wash bottle of distilled water Method 1 1. Set up the equipments as stated below. 2. Measure the exact 100.0cm3 of distilled water and add into 250cm3 conical flask. 3. Weigh about 0.10g of lithium. Record the exact mass of lithium using an appropriate format. 4. Remove the stopper, add the lithium to 100cm3 of distilled water in conical flask, and quickly replace the stopper. ...read more.

Middle

2. Using pipette 25.0 cm3 of the solution in the conical flask from method 1 into a clean 250 cm3 conical flask and add 5 drops of Phenolphthalein indicator. 3. Titrate with 0.100mol dm3 Hydrochloric acid. 4. Record the results in an appropriate format. 5. Repeat the titration to obtain consistence results. Show all of the results. 6. Record the average titre. Diagram for method 2 Hydrochloric acid Lithium hydroxide and Phenolphthalein indicator Results Table Trial 1 2 Burette Final 44.5 42 41.5 Initial 0 0 0 Volume used (titration) / cm3 44.5 42 41.5 Mean titration /cm3 44.5 + 42 + 41.5 = 128/3 = 42.7 Calculation LiOH(aq) + HCl(aq) LiCl(aq) + H2O(l) 1. Moles of HCl used in titration Moles = molarity x volume = 0.100 x (42.7/1000) = 0.00427 2. No. of moles of LiOH = 0.00427 as the ratio is 1:1. 3. No. of moles of LiOH present in 100cm 3 of the solution from method 1 = 25 /100 = 4 Therefore 0.00427 x 4 = 0.01708 4. ...read more.

Conclusion

I had to take three readings to get the sufficient mean titration result, which required a lot of time to do this. Accuracy By taking results for three times allowed me to gain a good average of the concentration. Also the use of three results meant that the reliability and the accuracy of my results were high. Problems encountered The main problem was that it was difficult to put the measuring cylinder full of water into the plastic box of water up side down to collect gas. The second problem was that I did not rinse the conical flask every time after each titration therefore more titration was required. And the titre readings were not similar. Improvements By looking at the above problems I would use the gas syringe to measure the hydrogen gas. I would rinse the flask out properly to ensure that it is fully cleansed and ready for the next part of the investigation. Extension As an extension to the investigation I could use other elements, to calculate the their relative atomic mass and compare them. ...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. Determination of the relative atomic mass of magnesium.

    Because, if the temperature is not standard, one mole of the hydrogen would not take up 24dm3, which would make the calculations inaccurate.

  2. Determination of the relative atomic mass of lithium.

    To improve the accuracy of my results the room temperature should be checked. Because, if the temperature is not standard, one mole of the hydrogen would not take up 24dm3, which would make the calculations inaccurate.

  1. Determination of the relative atomic mass of magnesium by back titration

    Weigh out accurately about 0.3g of the magnesium ribbon. 2. Pipette 50.0cm3 of the 1.0M hydrochloric acid into a 250cm3 volumetric flask. 3. Break the magnesium ribbon into small (about 1 cm) pieces and carefully drop it into the flask.

  2. Determination of the Relative Atomic Mass of Calcium

    * This method was only carried out once. To gain a respectable average and also to see if any anomalous results are gained, the method can be carried out at least 3 times. Method 2: This method was also not accurate as shown by the percentage error gained.

  1. The Determination of an Equilibrium Constant.

    reacted equals the amount of CH3COOH (C2H5OH) produced ?Number of moles of CH3COOC2H5 at equilibrium = 0.784 - 0.35 = 0.434 mole Number of moles of H2O at equilibrium = 5.556 - 0.35 = 5.206 mole 4 [CH3COOC2H5] = 0.434 / 0.25 mole dm-3 [H2O] = 5.206 / 0.25 mole

  2. Planning of Titration

    (Rinse 2 times to make sure only acid is present and nothing else in the burette to get accurate results). Also if water is left in the burette it will dilute the acid, which will give inaccurate results. * To fill a burette, close the stopcock at the bottom and use a funnel.

  1. Determination of the relative atomic mass of lithium.

    Obviously this would alter the result which means it is an error, it is an unfair test and that my results are wrong. Each and every source of error affects the results by different amounts. For example one of the most damaging errors in my opinion has to the bung along with the delivery tube.

  2. Determination of the Relative Atomic Mass of Lithium

    Lithium Hydroxide thus stoichiometry = 1:1 0.0112 mol of Lithium hydroxide = 0.0112 mol of Lithium 0.0112 mol of Lithium = 0.09g 1 mol of Li = 0.09 = 8.0g 0.0112 Thus the Relative Atomic Mass of Lithium is 8.0g mol-1 from experiment 2.

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