Lab#3 Separation of a Mixture of Solids Essay

There are various techniques to separate a mixture of compounds from each other. One of the commonly used way to isolate compounds from a mixture of two compounds is called extraction. This method of extracting two compounds from each other relies on the different solubility of the compounds in two different solvents.

This experiment combined all the knowledge of the previous labs performed throughout the semester. An unknown mixture containing an organic acid or base and an organic neutral compound in nearly equal amounts needs to be separated to its separate components. An understanding of solubility, extraction, crystallization and vacuum filtration is necessary in order to

The Vitamin C turned to a red/orange color with no physical/chemical reaction. For the salt the solution turned to an orange color with no physical/chemical reaction. With the Alka-Seltzer, the solution turned to a brown color with no reaction as well. Last but not least, the Baking soda turned to an orange/brown color with no reaction.

In order to show you why these students believe the mystery mixture is a combinations of NaHCO3 & C6H8O7 I will need to show you the mixture’s chemical and physical properties. The NaHCO3 & C6H8O7 mixture is a bright white color, and has a slight airy smell. The claim also has a powdery white substance or the NaHCO3. It also has small white spheres, that resemble the mystery mixture’s, which is probably the C6H8O7. The students have also learned through experimentation that if you leave the

Solub. Or Reaction w/ hot H20: no change observed from the cool water and is soluble

Me and my lab partner, obtained a mixture of a un known proportion from the instructor and then flow the guide line in our lab manual to separate the mixture by applying the separation method motioned in our lab manual pages 33-40 . In this experiment, the separation methods were decantation,

21) After all of the solid dissolves, move the flask from the hot plate and allow it cool to room temperature. After a while, crystals should appear in the flask.

The objective of this extraction experiment was to achieve a comprehensive understanding, as well as master the practice, of the technique of separating various individual components of a compound.

Heavy precipitate emerged immediately and solution turned white in color; solution then became opaque and turned light, bright blue in color.

The compound was tested for the presence of ammonium, carbonate, sulfate, chloride, and nitrate, as seen in Table 2. The nitrate test produced a precipitate, indicating the presence of the nitrate ion in the compound. At this point it was hypothesized that our unknown compound was calcium nitrate.

The percent mass of each component of the mixture was 23% iron, 61% sand, and 8.7% salt.

The melting point range of the unknown acid is most similar to the mixed range of the unknown acid and 2-chlorobenzoic acid, so the unknown acid is 2-chlorobenzoic acid.

After dissolving benzoic acid in 1.0mL CH2Cl2 and 1.0mL 10% NaHCO3 solution, two layers are created, the top layer is 10% NaHCO3 solution and the bottom is CH2Cl2.

This liquid is clear, has a fluid consistency similar to water, and has a strong odour that reminds me of alcohol.

Recrystallization was done to remove impurities from the sample. The percent recovery of benzoic acid during recrystallization is 23.02%. The difference between the pure and impure samples was observed by comparison of melting points. It was found that impure sample had a lower and wider melting point range of 120.1-122.2 (C). The pure sample melting point range was 121.3-122.5 (C). These ranges helped determine purity by comparing the known melting point of pure benzoic acid.