Analytical Chemistry

At the beginning of this topic, students are expected to apply their knowledge and skills they have acquired in previous topics of the Compulsory Part to plan and carry out appropriate tests for the detection of some common chemical species. Other than the common separation methods learned in earlier topics, students should know that liquid-liquid extraction and chromatographic methods can be used to separate a mixture of substances.

Students are also expected to understand that the determination of melting point and boiling point is an important way to indicate the purity of a substance. In addition, this topic stresses quantitative methods of analysis. Students should be provided with the opportunity to solve problems related to estimating quantities of substances, if possible in authentic situations. In this connection, investigations using different types of volumetric methods, which may involve acid-base reactions and redox reactions are conducted. On completion of this topic, students are expected to acquire skills related to quantitative chemistry, such as performing calculations and describing ways to minimise possible sources of error.

Modern instruments play a key role in chemical analysis nowadays. Students are expected to acquire a basic understanding of instrumental methods such as colorimetry for determining the quantity of coloured substances, infrared (IR) spectroscopy for identifying functional groups and mass spectrometry for determining molecular structures. Students should be aware of the limitations inherent in the use of conventional chemical tests in the detection of chemical species and hence appreciate the application of modern instruments in chemical analysis. However, in-depth understanding of the principles and detailed operation procedure of the instruments are not expected at this level of study.

Instead of learning a number of tests and analytical methods, students can select the most appropriate means to solve problems in different situations, and justify their choices. Together with the hands-on experience of investigating the nature and the quantity of chemicals, students are expected to understand the important role of analytical chemistry in daily life.