tailieunhanh - Modern Analytical Cheymistry - Chapter 3

The Language of Analytical Chemistry Các nhà hóa học phân tích trò chuyện bằng cách sử dụng thuật ngữ chuyển tải ý nghĩa cụ thể cho các nhà hóa học phân tích khác. Thảo luận và học hóa học phân tích, trước tiên bạn phải hiểu ngôn ngữ của nó. Bạn đang có lẽ đã quen thuộc với một số thuật ngữ phân tích, chẳng hạn như "chính xác" và "chính xác", nhưng bạn không có thể đặt chúng trong bối cảnh phân tích thích hợp của họ. Các từ ngữ khác, chẳng hạn như "chất phân tích" và. | Chapter 3 The Language of Analytical Chemistry A. nalytical chemists converse using terminology that conveys specific meaning to other analytical chemists. To discuss and learn analytical chemistry you must first understand its language. You are probably already familiar with some analytical terms such as accuracy and precision but you may not have placed them in their appropriate analytical context. Other terms such as analyte and matrix may be less familiar. This chapter introduces many important terms routinely used by analytical chemists. Becoming comfortable with these terms will make the material in the chapters that follow easier to read and understand. 35 36 Modern Analytical Chemistry analysis A process that provides chemical or physical information about the constituents in the sample or the sample itself. analytes The constituents of interest in a sample. matrix All other constituents in a sample except for the analytes. determination An analysis of a sample to find the identity concentration or properties of the analyte. measurement An experimental determination of an analyte s chemical or physical properties. technique A chemical or physical principle that can be used to analyze a sample. method A means for analyzing a sample for a specific analyte in a specific matrix. procedure Written directions outlining how to analyze a sample. 1A Analysis Determination and Measurement The first important distinction we will make is among the terms analysis determination and measurement. An analysis provides chemical or physical information about a sample. The components of interest in the sample are called analytes and the remainder of the sample is the matrix. In an analysis we determine the identity concentration or properties of the analytes. To make this determination we measure one or more of the analyte s chemical or physical properties. An example helps clarify the differences among an analysis a determination and a measurement. In 1974 the federal .