QUANTITATIVE ANALYSIS

Quantitative Analysis in Chemistry

Quantitative Analysis in Chemistry

Question 3 b

In order to ensure accuracy during the purification, I kept in mind that accurate weighing each compound is important. This helped me minimize the human errors.

During the synthesizing of aspirin, Paracetamol, hexaamine cobalt III chloride, copper I chloride and acetamide, I made sure to use a calibrated apparatus and I also times my experiment perfectly.

Question 4 a

The factors that affect the purity of the sample are:

Oxidation

Humidity and moisture

Dryness

Light and radiation

High temperature, etc.

Question 4 b

The technique is used to improve the purity/ accuracy of the compound that I made is recrystallization. I followed the below mentioned procedure:

I placed the crude drug on in a 100 cm3 beaker

I added 20 cm3 of water and heated it on a hot plate until the crystals dissolved

I then removed the beaker and allowed it to cool

When the crystals were visible I placed the beaker in a water bath

Now crystals were transferred onto a filter paper

The mass of the pure sample was determines by me.

Question 5a

Melting Point

The accuracy of the melting point is not questionable and it is highly reliable because the identification of two different compounds can be easily done with this method. The example of melting point analysis is the differentiation of Propanone and Propanoic acid. In order to minimize the number of errors in during melting point determination the following steps should be taken:

The melting point apparatus should be heated slowly so that the thermal equilibrium is maintained.

Calibration of the thermometer is an important step.

Distillation

Distillation method is a technique used in qualitative analysis. The accuracy in this method can be enhanced by adopting the following steps:

Addition of boiling chips will avoid violent boiling and entrapment of impurities into the solution.

The heating should not be too fast or vigorous. This causes contamination.

Crystallization and Recrystallization

Factors such as impurities and solvent level cannot be controlled during this technique but errors can be minimized by the adoption of the following steps. The example includes the recrystallization Paracetamol analysis

If the cooled crystals are not washed with a cool solvent some impurities may dissolve in the otherwise warm solvent. This compromises the accuracy of the end result.

The sample compound should be sufficiently heated so that there is no damage to either the impurities or the sample compound.

Question 5 b

The accuracy of the techniques used was critically sufficient. We acquired conclusive and valid results. This is claimed because the results were matched with the suggested results in the standard operating procedures. Moreover, when the purity was assessed, the melting point and boiling point and IR spectra were accurate. This proves that the accuracy of the procedures were conclusive.

Question 6

Purity

The purity of the Paracetamol product can be increased by using clean apparatus and pure solvent.

Yield

The yield of the Paracetamol production can be increased by filtering the sample at a lower temperature.

Atom Economy

The atom economy of the Paracetamol synthesis can be increased by choosing a more efficient reaction method of synthesis. Since the employment of p-amino phenol for the production of Paracetamol is ...