Experiment 1

PRE-LAB ASSIGNMENT

1. Write a paragraph what do you understand about polar solvents and give at least three examples of polar solvents.

Solvent is the term used for liquid. Meanwhile, polar solvent is a liquid with molecules that have partial electrical charges on them. The molecules in the liquid have different charges, which are positive and negative charge and they are chemically active. Examples of polar solvents include acetone, methanol, ethyl acetate and dichloromethane.

1. What is the meaning for the term immiscible solution?

Immiscible solution is a solution containing two liquids which cannot be mixed, combined or dissolved with each other. The bond that are holding the two different liquid cannot be broken down to form a whole new bond where both of the liquids can exist as one cohesive solution and thus it is named as immiscible solution.

1. Draw a diagram of separating funnel and a simple distillation apparatus set up.

RESULTS:

Table 1: Volume of diethyl ether and toluene before and after distillation

CALCULATION:

Percentage recovery of diethyl ether

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Percentage recovery of toluene

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DISCUSSION:

Based on the experiment, the immiscible solution that has been separated were toluene and water. Ether was used as a medium to separate toluene from water in this experiment. During the experiment, both water and toluene as well as ether were inserted in the separating funnel where two layers started to form. The aqueous and organic compound layer can be determined by the density of the solution. The denser solution will be at the bottom layer and the less dense solution will be at the top layer. Water is denser than toluene and ether and thus, it is in the bottom layer. However, a testing was done to prove it. The solution was tested with distilled water where if the distilled water and the solution mix together, it is proved to be an aqueous solution and vice versa. Based on the testing done, the liquid at the bottom layer is the aqueous solution and the liquid at the top layer is the organic compound solution.

After the aqueous solution and the organic compound solution have been separated, the organic compound solution is filtered by using a drying agent which is magnesium sulphate in order to further discard the lingering water that remain within the organic compound. As stated in the website of UCLA, the drying agent need to be measured sufficiently in order not to over drying the solution which may ended up in losing the product. The drying agent is added in a small amount at first and the solution was swirled. The solution turned translucent which mean that the drying agent added is adequate and it is understandably dry.