数字比色分析法在大学本科化学实验中的应用——铁-磺基水杨酸配合物稳定常数的测定

Feasibility of Applying Digital Colorimetric Method to Experiments for Chemistry College Students: Determination of the Stability Constant of Iron(Ⅲ)-Sulfosalicylic Acid Coordination Compound

数字比色法是近年来发展起来的一种检测方法。“铁-磺基水杨酸配合物稳定常数的测定”是大学无机化学中的经典本科学生实验。将数字比色法应用于该学生实验并与常规的分光光度法分析结果进行了对比。首先,探究了数字比色法的数据采集,即照片拍摄条件的因素控制。其次,通过数据比较分析了数字比色法的应用特点。结果显示,数字比色法的灵敏度介于目视比色法与分光光度法之间。该方法对较小的颜色差异分辨能力不足而对比较明显的颜色变化区分能力较好。在本科实验教学中,将该方法应用于颜色变化梯度明显的化学反应体系可获得较好的分析结果。

“Determination of the stability constant of iron(Ⅲ)-sulfosalicylic acid coordination compound” is an important inorganic experiment for the chemistry and chemical engineering college students. Digital colorimetric method was developed recent years by using smart phone and APP to accomplish data analysis of chemical reactions which accompany with color changes. In this work, digital colorimetric method was tried to apply to the aforementioned experiment. The condition control of the data collection, namely, the photograph process of the digital colorimetric method was investigated firstly. Then results obtained was compared with the conventional absorption spectrophotometry. Based on that, features of the application of digital colorimetric method were discussed. It was showed that digital colorimetric method had relatively low resolution to slight color difference and so should be applied to processes with relatively obvious color change.