Abstract A new smartphone imaging digital colorimetric method for determination of Cr(Ⅵ) in water was proposed. The Cr(Ⅵ) from aqueous solution reacts with diphenylcarbazide to form a color complex, then the digital images from the solution above was captured by a smartphone and imported into the Photoshop software to read the brightness value of green channels. The experimental data showed that brightness value is linearly correlated with the concentration of Cr(Ⅵ) in solution. The influential factors such as shooting mode and image reading mode were studied and optimized. The results were consistent with the spectrophotometric method with the recovery of 98.0%~102.0%. This obtained method is rapid, accurate, easy to operate and can be used in on-site analysis without professional instruments. The presented method of students' own smartphones as only testing equipment can greatly stimulate students' interests in experiment and innovative spirit.
DING Zong-Qing, ZHU Sheng-Ping, ZHOU Xiang-Yu. Determination of Cr(Ⅵ) in Water Samples by Smartphone Imaging Digital Colorimetric Method[J]. Chinese Journal of Chemical Education, 2017, 38(4): 68-71.
