First is pleased with the teacher together to learn chemistry, a semester is going to end, I also learned a lot. Here, I will simply a statement of this discipline to my new knowledge. No doubt, English teaching methods so that I can not accept. The first face is that those chemistry even Chinese didn't fully understand the vocabulary. For example, titration, the equilibrium constant and so on monochromator. But as the teacher said, perhaps chemistry without the help of our future work, but more words on the back after going abroad is beneficial. Therefore, to master the necessary word is to learn chemistry is necessary, it is a good opportunity to exercise the back word. Secondly, for the titration reaction I have a deeper understanding. Previously only know the acid-base titration and redox titration. Now, through the study of EDAT we know to have direct titration, indirect titration, back drop and displacement titration. And sometimes we need a suitable masking agents joined to help our titration test. (concept: masking agent a masking agent is a reagent that protects some component of the analyte from reaction with EDTA) finally, I also learn some new knowledge of light. For example, the reciprocal number equal to the wavelength. Know Ta masking agent is a light transmittance of reagent that protects some component of the analyte from reaction with EDTA A T is the) and the absorbance of fraction of incident light that passes through a sample. T= p/p0. If T=0, substance is opaque; if T=1, substance is transparent. A= -logT. The higher the absorbance, the less light is transmitted through a sample. also in the Bill's law of A= epsilon BC (epsilon is symbol of molar absorptivity molar absorption coefficient, B is symbol of pathlength C is symbol of optical path length, the concentration of concentration.)