一、方法的基本原理(1)方法的基础光度滴定是以连续测量滴定过程中,待测溶液吸收光量的变化为基础。吸收的光流能量以光密度(D)或透过率(T)表示;而用光电比色计或分光光度计测量。光密度与溶液中吸收物质的浓度之间的线性关系,是方法的使用条件。如果待测溶液对光的吸收,服从Beer定律,则在给定的波长下进行滴定时,吸收组分浓度的变化,就反映出光密度的变化。在D=f(v)上作图(v表已知浓度的滴定剂的体积),即可得出表示滴定过程的两条相交的直线,而以两 First, the basic principles of the method (1) the basis of the method Photometric titration is based on the continuous measurement of titration process, the changes in the amount of light absorbed by the test solution. The energy of the absorbed optical flow is expressed in terms of optical density (D) or transmittance (T); measured with a photoelectric colorimeter or a spectrophotometer. The linear relationship between optical density and the concentration of absorbent material in solution is the method’s conditions of use. If the solution to be tested for the absorption of light, subject to Beer’s law, when the titration at a given wavelength, the change in concentration of the absorbing component reflects the change in optical density. A plot of the volume of titrant of known concentration at v = f (v) yields two intersecting lines representing the titration process,