• Join over 1.2 million students every month
  • Accelerate your learning by 29%
  • Unlimited access from just £6.99 per month
Page
  1. 1
    1
  2. 2
    2
  3. 3
    3
  4. 4
    4
  5. 5
    5
  6. 6
    6
  7. 7
    7
  8. 8
    8
  9. 9
    9

The relative atomic mass of lithium

Extracts from this document...

Introduction

COURSEWORK Background information I'm going to produce a piece of coursework, which determine the relative atomic mass of lithium. Two methods are going to be used to approximate the relative atomic mass of lithium. 1) In the first method the RAM (Relative atomic mass) of lithium is determined by the Volume of hydrogen gas produced. 2) In the second method the RAM of lithium is determined by titrating the lithium hydroxide produced. To some extend, I think that the first method is the most practical and less complicated, because the less calculations has to be done. Hence it is more easer to measure the volume of hydrogen gas. Test-1 My mission was to find out the atomic mass of lithium. I took a sample and weighted it, removed parts of the sample so that it would weigh approximately 0.100g. The oil was removed from the sample by filter paper wiping it with,so no more oil can be seen. The scale was not a very sensitive one and we could weigh with a margin of error of 0.01g. Then I placed the sample in a beaker that contained 100 cm3 of distilled water. ...read more.

Middle

5) Then the average titre is recorded. Results I gathered a large enough range of results to make accurate observations from. The experiment was repeated until consistent results were obtained; Run 1 Run 2 Run 3 Initial volume (cm3) 1.3 2.7 1.4 Final Volume (cm3) 39.7 38.4 40 volume Titre used (cm3) 38.4 35.7 38.6 Mean titre (cm3) 56.35 Burette reagent HCl mol dm -1 Pipette solution LiOH mol dm-1 indicator Phenolphthalein mol dm -1 Analysis Calculation: 1st test- by measuring the volume of hydrogen produced A mass of 0.07 of lithium was used, which gave 116Cm3 of H2 * Calculate the number of moles of hydrogen 116/24000 = 0.0048 mol of H2 2Li (s) + 2H2O(l) ----->2LiOH(l) + H2(g) so, 2* 0.0048 = 0.0097mol of Li using the formula to find the RAM of Li --------> Mole = mass/Ar or Mr so, 0.07/0.0097 = 7.2g of Li The answer is very close to the standard RAM of Li Error calculations, 7.2*100/7=102.86 - which means that there is 2.86% error in the first method 2nd test - by titrating the lithium hydroxide with HCl. From the results table the mean titre is found by adding the runs altogether that divide the by 2 Mol =vol/1000*concentration = 38.4+35.7+38.6=56.35 /2 = 28.175cm3 = 28.175/1000*0.100=0.002818mol = ...read more.

Conclusion

if the methods had more details in it then this will inpruve the accuracy of the experiment. The method didn't give enough information of how to calculate the results, so i strugeled a bit, but in the end i worked out with the help of the book. To minimise the errors the method should have explained in detailed the performers that the experimenter has to carry out. To make the experiment the most accurate possible the equipment should be the more advanced ever, and variables should be pure with out any mixture. For further improvement a freshly cut pure lithium should be used, this could be done by putting the lithium in the vacuum before transferring it into the conical flask. A freshly cut pure lithium means having accurate results (out comes). Also after introducing the lithium into the conical flask the stopper should be replaced very quickly so a low minimum gas escapes. Then to measure this gas a more accurate apparatus should be used like(Eudiometer ).The mass balance despite taking quick readings, was not the most accurate possible, so to improve the accuracy of the experiment a more advanced electronic mass balance should be used. I think more time is also needed. If i was doing the experiment again i would like a bite more time to perform the experiment as this would improve the accuracy of the experiment ...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 Classifying Materials 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 Classifying Materials essays

  1. The rates of reaction between CaCO3 and HCL

    So using the mean method of working out an average was not accurate. Purity Calculations: From the results of the graph without studying the data west looks to be purer, this is based on the scientific theory that more produced yielded form a reaction the more atoms available to react.

  2. Affect of concentration on reaction

    1st Mass Loss (g) 2nd Mass Loss (g) Average Mass Loss (g) 0 0.0000 0.0000 0.0000 5 0.2480 0.2590 0.2535 10 0.2650 0.2710 0.2680 15 0.2730 0.2800 0.2765 20 0.2810 0.2890 0.2850 25 0.2880 0.2970 0.2925 30 0.2950 0.3040 0.2995 35 0.3010 0.3110 0.3060 40 0.3060 0.3170 0.3115 45 0.3110

  1. Relationship between mass of MgO and its formula

    Find the masses that combine (in grams) by experiment 2. Change grams to moles of atoms 3. This tells you the ratio in which atoms combine 4. Then write the formula down Below are the empirical formulas for the experiment I carried out.

  2. Bonding Practical

    If it is not definitely clear whether the sample has dissolved I will test the pH of the solution. If the substance has dissolved the colour of the mixture will change from the colour of distilled water. The only equipment needed for this experiment would be a beaker, a stirring rod and some universal indicator.

  1. What "Carried the Trick"? Mass exploitation and the decline of thought in Ray Bradbury's ...

    Moreover, the current debate about political correctness also helps shape how we read Bradbury. Awareness of these controversies is certain to make us even more aware of Bradbury's treatment of minority pressure. The threat of "mass culture" has been recognized by Peter Sisario (210), John Huntington (136), and David Mogen

  2. The role of mass customization and postponement in global logistics

    the manufacturing process; they are: * Post Delivery - products are stocked at retail outlets as in mass production; product design facilitates customer involvement and modifications after delivery, * Deliver to Order - products are assembled and stocked; firm responds to customers' delivery specifications interests; product is packaged and distributed

  1. Determining the Relative Atomic Mass of Lithium.

    This means that the timing must be perfect in order to have accurate results. The overall average Ar was close to the actual Ar of Lithium, the overall average Ar was 7.1. There are other factors that could have contributed to the inaccuracy in the results, these are: - *

  2. Variability of Relative Stability of Oxidation States.

    However, it is not stable, for instance, Al is reactive at normal temperature. It can be oxidized by oxygen in the air. The oxidation numbers of B and Al are +3 in almost all their compounds. However, the heavier elements in the group are more likely to keep their s-electrons

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