Qualitative Test for Elements in Aspirin
Autor: Jannisthomas • December 11, 2017 • 879 Words (4 Pages) • 1,142 Views
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Table 4: Qualitative test for Halogens
Test Sample
Treatment
Observation
Inference
Fused Aspirin & Na(metal)
Immerse with copper metal
No color change of green observed
No Halogen present
Beilstein test was used to determine the presence of halogens in organic samples. Theoretically, an organic halogen compound tells a green flame color when burned upon the surface of a copper wire. When surface copper wire was burned up, a formation of copper oxide was obtain then this copper oxide will react to the halide to form cuprous halide, which burns a green flame. In this experiment, as the burned copper wire was immersed in the fused solution, immediately, the copper wire was heated in the alcohol lamp. As a result, no color change in the flame of the alcohol lamp was observed indicating that no halogen was present in the aspirin. This test showed a negative result for the compound.
Table 5. Qualitative test for Sulfur
Test Sample
Treatment
Observation
Inference
Fused Aspirin & Na(metal)
5 drops 10% NaOH + 2 drops 5% Pb(CH3COO)2
No formation of black precipitate observed
No Sulfur present
Theoretically, lead acetate test was use for the determination of sulfur in the organic sample. In lead acetate test, the presence of sulfur is detected by the production of brownish-black lead sulfide when organic sample containing sulfur is treated with lead acetate in the presence of acetic acid. The use of acetic acid is to prevent other lead salts to be formed. In this case, NaOH was used for the formation of sodium sulfide that was needed for the formation of lead sulfide as brownish black precipitate when the solution was heated. In this experiment, there was no formation of black precipitate was observed, thus, no sulfur present in the sample. The lead acetate test for sulfur showed a negative test for the laboratory prepared aspirin.
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