- Clean a crucible over a Bunsen flame for five minutes and allow it to cool to room temperature.
- Weigh the crucible, and measure a 0.3g sample of magnesium in it.
- Heat the crucible with its contents with the cover on for about 5 minutes.
- Use the tongs to displace the lid slightly to allow air flow, and heat strongly for 10 minutes.
- Remove the flame and somewhat cool, and add 2-3 drops of water.
- Heat gently and then strongly with lid slightly displaced for 5 minutes
- Cool crucible and then weigh.
- Record your data and calculations
Data:
The following data table, table 2, was created after the weights were obtained.
Weight of the crucible 19.83g
Weight of the crucible & Magnesium 20.12g
Weight of the Magnesium 0.29g
Moles of magnesium 0.011929
0.29g Mg x (1 mol Mg / 24.31g Mg) = 0.011929 moles
Weight of the crucible & Magnesium oxide 20.31g
Weight of oxygen 0.19g
Moles of oxygen 0.011875
0.19g O x (1 mol O /16g O) = 0.011875 moles
Table D
The data from table D shows that the empirical formula for magnesium oxide is MgO.
Analysis:
The masses obtained from both the magnesium and the magnesium oxide were reasonable. As evident from Table D, the magnesium had 1.0045 moles which when compared to 1 mole of oxygen, was way less than a 1% error. This resulting indicates that the empirical formula for magnesium oxide is:
2Mg + O2 => 2MgO
The ionic bond between one magnesium and one oxygen atom formed magnesium oxide. The compound that was created was a white powder.
Conclusion:
The formation of a compound was successful. A mol to mol ratio of 1 to 1 was recovered. The empirical formula that was determined in the lab was the correct empirical formula for the creation of magnesium oxide.
