• 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. Lab 1 - Determining Hydrate Formulas

    Sulfate (ZnSO4) after 2nd heating 17.30g There is none because I used a digital device to determine the mass, so I can't have possibly made any mistakes. Mass given by weighing machine in grams (g) � 0.005g *Percent of Uncertainty = (absolute uncertainty)

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

    Therefore, I will use the mathematical procedure to find the heat of combustion of magnesium. We have determined the following values for the two reaction and one is given to us. ?H 1 = Mg(s) + 2HCl (aq) � MgCl2(aq)

  1. An Experiment to Determine the Empirical Formula of Lead Iodide

    iodine: moles of lead Ratio of Pb to I = moles of lead / moles of iodine Ratio = (7.29 x10-4/7.29 x10-4) : (7.29 x10-4 / 1.11 x10-3)= 1: 1.5 Uncertainty: Moles of lead: 0.71 % Moles of iodine = 2.18 % Total uncertainty = 2.18 % + 0.71 %

  2. 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)

  1. Chemical Formula Lab

    This probably happened because the flame was close to the bottom of the cubicle and was set at high due to time restrictions; and so some of the zinc chloride molecules at the bottom of the cubicle probably had enough energy in order to evaporate.

  2. Finding thr Percentage Composition of Magnesium Oxide

    Answer the Testable Question that was posed at the beginning of this investigation. Support your answer with evidence.

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