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Potassium Dichromate

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Analysis:
Safety Analysis:
A number of safety precautions needed to be adhered to in order to maintain a safe and controlled working environment. Acetic acid and potassium dichromate are two examples of hazardous substances used throughout the practical, with their effects being intense redness, potential blisters, inhalation is potentially irritant to lungs etc. In order to prevent all contact with these substances, paper towels were used to wipe the glassware in order to remove any traces. Sulfuric acid was the most hazardous substance used in the practical, hence the use of a fume hood was required due to its harmful effects in case of inhalation. Its corrosive and irritant nature could be of great damage onto skin, hence potential skin
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In this case, the highest polarity exists in the carboxylic acid due to the presence of the double bonded oxygen and hydroxyl functional group (Figure 3). Furthermore, the molecule contains a hydroxyl functional group from which hydrogen can induce hydrogen bonding, the strongest type of intermolecular bonding. Dispersion forces also exist between neighbouring molecules as electrons constantly orbit around the atom. Acetic acid can be predicted to have the highest boiling point and will require the largest input of heat to be able to evaporate and undergo esterification. Its solubility in water is high due to the hydrogen bonding occurring, which is further enhanced by the position of the hydroxyl at the end of the molecule. Propan-2-ol (Figure 4) can be predicted to have a relatively high boiling point due to its ability to induce hydrogen bonding which promotes its solubility in water. However, its boiling point is not anticipated to be as high as the acetic acid as propan-2-ol lacks a carbonyl functional group. Furthermore, the reacting hydroxyl remains in between carbon chains and hence its interaction with water is less efficient as surrounding atoms restrict this effectively. As a result, dispersion forces occur less frequently and hence the secondary bonding can be broken easily in comparison to the carboxylic acid.…show more content…
Although it contains a carbonyl bond additional to a covalently-bonded oxygen, water is able to form strong hydrogen bonding with two of its hydrogen atoms. Propyl ethanoate is only able to form dipole-dipole bonding in addition to dispersion forces in their intermolecular interactions. In contrast, water is able to form strong hydrogen bonds with surrounding molecules while conforming to dispersion forces. It follows that water will require a higher boiling point in comparison to isopropyl ethanoate due to its ability to form H-bonds with surrounding molecules, which require a higher heat energy input to break. As the ester’s polarity is low in comparison to water, it is unable to dissolve completely in water and therefore, after esterification, the aqueous and organic layers are separated as seen in Apparatus 2. The layer of ester is on the top as it is less dense than water due to its lower polarity in comparison to water, which remains in the aqueous layer at the bottom. (Science.uwaterloo.ca,
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