摘要
溶液濃度檢驗是相當重要的科學實驗，例如在檢驗未知濃度的酒或食用油，透過各種檢驗方式，可以得知是否添加甲醇或劣質油。濃度檢驗的方式有很多種，有各種滴定法、色層分析法和光譜光度分析。前兩種方法比較偏向化學反應，光譜光度分析則是和光的吸收反應有關。光通過介質會有各種交互作用，而光被吸收的多寡和通過介質的距離，以及介質濃度有關，主要理論稱為朗伯比爾定律。透過對光的分析可以推測待測溶液的濃度。通常光譜光度分析實驗會用上光譜儀，本論文無須使用光譜儀，而是採用比色法，直接透過智慧手機的app功能，演示光被不同濃度介質吸收的特性，並根據已知濃度的液體實驗，得到濃度與光強度的線性關係，藉此可以估算待測液體介質的濃度。
並列摘要
Measurement of the concentration of the mixture is one of the important science experiments, e.g. unknown concentration of the wind and cooking oil. There are many methods to measure the concentration such as titrations, chromatography and spectrophotometry. The spectrophotometry is the quantitative measurement of the reflection or transmission properties of a material as a function of wavelength. The absorption of the light in the medium depends on the distance of the penetration in the medium and concentration of the medium. It called Lambert-Beer's law. We can analysis the absorption of the light in the medium to derive the concentration of unknown medium. Usually people use expensive spectrometers in experiment. We adapt colorimetry to measure the concentration here. There are few smartphone colorimetry applications to analysis the absorption of the color of light quantitatively and demo the Lambert-Beer's law. We can fit the data and get the molar absorptivity (K) which can estimate the concentration of the unknown medium further.