Empirical Formula of Magnesium Oxide

Data Collection

Raw Data:

Magnesium ribbon: before the ribbon was cleaned it was malleable, coarse, a little shiny, but after it was cleaned with the steel wool it remained malleable but became smooth and very shiny.

Magnesium oxide: after the reaction had occurred in the crucible magnesium oxide formed into a dull, white, clumpy powder which had grey and black patches and resembled a coil shape

The reaction: when there was actually a reaction the content inside the crucible began to glow an orangey red shade and towards the end of the reaction white opaque smoke was escaping.

This table is the recording of the measurement obtained throughout the lab

Processing Raw Data:

Find the average mass of oxygen in the experiment

Trial 1:

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Trial 2:

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Trial 3:

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Trial 4:

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                                              =

Therefore, the average amount of oxygen obtained throughout the trials was 0.08g±0.02g

As a percent uncertainty:

% uncertainty of experimental mass of O2

Therefore, the average amount of oxygen obtained throughout the trials was 0.08g±0.02g or 0.08g±25%

Find the average mass of magnesium in the experiment

Trial 1:

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Trial 2:

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Trial 3:

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Trial 4:

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                                              =

Therefore, the average amount of magnesium obtained throughout the trials was 0.2g±0.02g

As a percent uncertainty:

% uncertainty of experimental mass of Mg

Therefore, the average amount of magnesium obtained throughout the trials was 0.2g±0.02g or 0.2g±10%

This table summarizes the differences calculated above

Determining the empirical formula of magnesium oxide

Calculate the moles of O present Magnesium oxide 

 = 0.005 mol ± 25.06% of O

Therefore there are 0.005 mol ± 25.06% of O in the magnesium oxide

Calculate the moles of Mg present Magnesium oxide

= 0.008mol ± 10.04% of Mg

Therefore there are 0.008mol ± 10.04% of Mg in the magnesium oxide

Determine the mole ratio

       

       

Therefore, the experimental empirical formula of magnesium oxide is: Mg2O3

However the literature empirical formula of magnesium oxide is: MgO

Determining the percentage composition of magnesium oxide

Determine the average mass of the magnesium oxide

Trial 1:

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Trial 2:

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Trial 3:

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Trial 4:

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                                              =

                                             

                                              =

Therefore, the average mass of magnesium oxide obtained throughout the trials was 0.28g±0.02g

As a percent uncertainty:

% uncertainty of experimental mass of MgO

Therefore, the average mass of magnesium oxide obtained throughout the trials was 0.28g±0.02g or 0.28g±7%

Determine the percent composition of Magnesium Oxide

Therefore, 70% of the experimental magnesium oxide is made up of magnesium and the other 29% of the experimental product is made up of oxygen.