We know that water with many Filter Pipette Tips will have a very adverse effect on our chemical analysis. Ultrafiltration technology is usually used to remove large molecular biologically active substances, such as heat sources (results <0.3MΩ. In addition, in order to obtain good reproducible results, it is necessary to use pure water that can maintain stable water quality. Generally, the more impurities in water, the higher the conductivity of water. Deionized water: conductivity is usually between 1. In addition, the resistivity value will change with the ionization constant of water, so it will be affected by the water temperature. Typical applications include the cleaning of glassware, autoclaves, constant temperature and humidity test chambers and water for washing machines. Microorganism E. This is because water molecules can combine with ions to produce 'hydrated ions.cm (mega ohm-centimeter). D. For example, the resistance value of ultrapure water at 25°C is 18.248MΩ. are often used to supplement the important parameters of water quality. Therefore, most of the pure water systems on the market, whether imported or domestic, are designed according to these standards.cm. Organic matter C. Ultra-pure water. Generally, it can be determined by ion chromatography or atomic absorption spectroscopy. Particulate matter D.2MΩ. 2.cm, and at 100°C it is 1.' The radius of the ions is very small, and the highly charged ions will interact strongly with the water molecules, which are closely arranged around the ions. With the increased sensitivity of the analytical system used in experiments, there is a higher requirement for the purity of water. Electrolyte B. Because the centers of positive and negative charges are inconsistent, they belong to polar molecules. Classification standard of pure water Laboratory pure water can be divided into 4 conventional levels: pure water, deionized water, laboratory grade Ⅱ pure water and ultrapure water pure water: the purification level is the lowest, usually the conductivity is 1-50μs /cm.2MΩ.The basic properties of water 1 water molecule (H2O) is formed by bending and bonding 1 oxygen atom and 2 hydrogen atoms. Therefore, the resistivity value compensated to 25 ℃ should be used as the measurement standard. At the same time, my country also has corresponding pure water standards: China's national electronic grade ultra-pure water specification