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

Determining the empirical formula of magnesium oxide lab

Extracts from this document...


Determining the Empirical formula of Magnesium Oxide Folawiyo Laditi etermine the empirical formula of maglculate the empirical formula of the oxide Masses and Qualitative data Observed throughout the experiment: Trial Number Mass of crucible (g) �0.01ical formula of Magnesium Oxide Mass of crucible and magnesium ribbon (g) �0.01 Mass of crucible and Magnesium ribbon after combustion (g) �0.01 Qualitative Observations 1 9.39 9.49 9.56 -Lid for crucible smaller than it so some air may have leaked in -flame was bending, not directly under crucible -white substance that crumbled easily left in place of magnesium ribbon -the magnesium ribbon itself was slightly lustrous, very thin and malleable 2 9.42 9.55 10.02 -lid smaller than crucible so air may have leaked in -white substance looking nothing like magnesium ribbon left 3 9.44 9.58 -Crucible broke so unable to take the last mass Data Processing: Below are other tables used to help calculate the empirical formula of the oxide: Trial one: Magnesium Oxygen Mass/g 9.49g-9.31g=0.10g 9.56g-9.49g=0.07g Moles /mol 0.10g/24.31gmol-1 =0.004114mol 0.07g/16.00gmol-1 =0.004375 Simplest ratio ...read more.


This means that the uncertainty for the number of moles of oxygen is �0.001269mol. Table two; After calculations for uncertainties for the moles of both elements were made, the uncertainty for the moles of magnesium was �0.000823mol and the uncertainty for oxygen �0.001269mol Since the uncertainties for the simplest ratios are not relevant, they were not calculated. The percent error for the first trial is: 6% The percent error for the second trial is: Conclusion: The empirical formula for magnesium oxide is MgO1.The empirical formula for one of the trials for this lab had this, but the other Mg6O5, which is relatively close. Even though the percent error for the second experiment seems large, I believe this is due to the fact that very small mass values were being worked with, as well as the fact that the percent error could only be calculated through the ratio, whereas the empirical formulas seem to indicate that the data is more accurate. ...read more.


There are a few ways to improve and avoid the above errors. It is unlikely that a more accurate scale could be used but since the experiment works with such small values, this would definitely be more appropriate. Also it would be best to use another crucible or completely clean out the original in order to avoid the error from the second trial. I think the experiment should be completely more times to make more accurate assumptions as to whether or not how well the crucible was cleaned after the initial trial had an effect on the second. There is a very slight possibility that incomplete combustion did not occur, but increase the accuracy of the experiment it would be best to expose the magnesium as much as possible to oxygen. There may also be impurities in the magnesium ribbon, despite the fact that it was cleaned with steel wool. If making sure the sample was purely magnesium that should be taken into account as well. 1 (TrueKnowledge, 2011)http://www.trueknowledge.com/q/what_is_the_chemical_formula_for_%22magnesium_oxide%22) ?? ?? ?? ?? ...read more.

The above preview is unformatted text

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

  1. Experiment - The Empirical Formula of Magnesium Oxide

    Qualitative Observation Photo 2: Reaction taking place At the beginning of the reaction, there were not any changes. Meanwhile, the lid was lifted twice. A few minutes later, the magnesium started glowing brilliantly (see the photo above). It glowed for a while until it stopped naturally.

  2. Empirical Formula of Magnesium Oxide

    Mg = Therefore the molar mass of Mg is about 24.3g �0.01g or 24.3g �0.04% Calculate the moles of O present Magnesium oxide = 0.005 mol � 25.06% of O

  1. Hesss Law Lab, use Hesss law to find the enthalpy change of combustion of ...

    The average result for all the three results is 549 kJ/mol, which can be accounted by with the uncertainty we had in the experiment. EVALUATION There were several discrepancies which could have potentially affected the outcome of the experiment and which will translate into the inaccuracies I had in my final result.

  2. Enthalpy of Combustion of Alcohols Lab

    of Carbons - 1)] Through the experiment, we were able to determine the enthalpy change of combustion of methanol, ethanol and butan-1-ol. Although we had random errors involved, the systematic errors contributed far more in the final percentage error than the random errors.

  1. Lab Experiment : The change in mass when magnesium burns. (Finding the empirical formula ...

    + 0.0001 =24.5431g Final mass of (MgO) inside crucible with lid in grams + 0.0001=24.7389g Processed Data: Percentage uncertainty= 0.04% 1.Mass of magnesium (in grams) + 0.0001= 0.3557g (The mass of magnesium ribbon = The mass of the crucible, lid and magnesium- mass of the crucible and lid)

  2. Discovering the formula of MgO

    =0,001+0,001=±0,002 Mass of Oxygen== (Mass of product)-(Mass of magnesium) Uncertainty in mass of oxygen= (Uncertainty in mass of product) + (Uncertainty in mass of magnesium) =0,002+0,001=±0,003 Percentage composition of oxygen= (Mass of oxygen/Mass of product)*100 Conclusion and Evaluation: Formula of magnesium oxide suggested by our Experimental results: From our results we can see we obtained values closer to 40%

  1. Measuring the fatty acid percentage of the reused sunflower oil after numerous times of ...

    solution with alcoholic KOH which is the process adding KOH with a burette into the solution until the colour pink stays for 30 seconds. 8) I measured the volume of alcoholic KOH which I used to titrate the solution at the end of the titration which means 30 seconds stable colour of pink.

  2. Finding the empirical formula of magnesium oxide

    22.60-22.43=0.17 22.62-22.45=0.17 Number of moles, oxygen/ mol = 0.0123 = 0.0123 Empirical formula of Magnesium oxide Mg : O 0.0123: 0.0106 1.1604: 1.000 Nearest whole number 1 : 1 MgO Mg : O 0.0123: 0.0106 1.1604: 1.000 Nearest whole number 1 : 1 MgO Aspect Experiment 1 Experiment 2 Experimental

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