The temperature of the gas phase rises again until it reaches the boiling point of a second content in the mixture and so on. By simple microscale distillation, we purified an unknown organic compound and then identified the unknown organic compound by using the boiling point and density measurements. Procedure/Results 5 mL of the unknown impure organic A was collected in an Erlenmeyer flask. A simple distillation apparatus was assembled and 3 mL of the unknown impure organic A was transferred into the distillation flask along with 3 boiling chips.
A thermometer was then suspended down the middle of the condenser to record the distillation temperature. The mixture was heated gently and a pure solvent started to collect in the distillation flask. Two different fractions were collected. The first one was the forerun, which was collected before the temperature stabilized and the second one was when the temperature of the boiling compound began to stabilize. The unknown impure organic A was identified using density and boiling point measurements collected.
Another simple distillation apparatus was assembled to find the boiling point of the unknown impure organic A. 3 mL of the unknown impure organic A and 3 boiling chips were transferred into the distillation flask and heated gently until the substance started to boil. The unknown impure organic A produced 0. 3 mL with a boiling point of 55°C for fraction one, which resulted in the density to be 0. 86 g/mL. 1. 2 mL was produced for fraction two with a boiling point of 58°C, resulting in a density of 0. 3 g/mL. The unknown impure organic A was then identified as acetone. Acetone has a boiling point range of 56-57°C and a density of 0. 791 g/mL. The observed boiling point range was 49-52°C with a volume of 2. 4 mL and a mass of 1. 71 g, resulting in a density of 0. 713 g/mL. Discussion: Acetone has a boiling point range of 56-57°C and a density of 0. 791 g/mL. The unknown impure organic A was identified as acetone due to having a boiling point range of 49-52°C and a density of 0. 713 g/mL.
The Term Paper on Melting Point Determination
Identifying an unknown compound can be a difficult task. In identifying a compound, researchers often measure several physical properties: melting point, boiling point, density and observes a few chemical properties: reactivity, acidity, basicity of the compound. The reason for determining several chemical and physical properties of the compound is that it is quite possible for two different ...
The boiling point range of the unknown impure organic A was lower than acetone’s actual boiling point range by 4-7°C, but was close enough to be identified as acetone because the density was only 0. 078 g/mL lower also. Therefore, both the density and boiling point measurements were good methods to use to identify the unknown impure organic A. Since the product wasn’t in exact value to acetone, errors could’ve occurred in the experiment. The boiling point could have still been trying to increase when we thought it had stabilized at 52°C, or liquid could’ve been lost due to spillage in transferring it to the distillation flask.
Conclusion The objective of the experiment was to identify the unknown impure organic A with the boiling point and density measurements by using a simple microscale distillation to purify it. Our results correctly identified the unknown impure organic A (with few errors) and proved the distillation process valid. This experiment could be improved by recording more fractions, or repeating the fractions several times and recording the boiling point more than once to improve accuracy.
