In Singapore, there are several ways to test purity, especially when it comes to food, water, and pharmaceutical products. Here are three common methods used for testing purity in Singapore:

1. Laboratory Testing: Laboratory testing is a reliable method to determine the purity of various substances. In Singapore, there are accredited laboratories that specialize in analyzing different types of samples. These laboratories use advanced equipment and techniques to detect impurities and measure the purity of substances accurately. For example, food products can be tested for additives, contaminants, or adulterants, while water samples can be analyzed for chemical composition, heavy metals, or microbial contaminants.
2. Spectroscopy: Spectroscopy is a technique used to measure the interaction between matter and electromagnetic radiation. In Singapore, spectroscopic methods such as infrared (IR) spectroscopy, ultraviolet-visible (UV-Vis) spectroscopy, or nuclear magnetic resonance (NMR) spectroscopy are commonly employed to analyze the purity of substances. These methods can help identify specific chemical compounds or determine the composition of a sample, thus indicating its purity.
3. Chromatography: Chromatography is a technique used to separate and analyze the components of a mixture. High-performance liquid chromatography (HPLC) and gas chromatography (GC) are widely used in Singapore for purity testing. These methods can separate different substances in a sample and provide quantitative measurements of their concentrations. By comparing the obtained results with established purity standards, it becomes possible to assess the purity of a sample accurately.