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Chemistry

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Chemistry

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Analytical Chemistry

Using Standards to Measure Unknowns

Description

Calibration curves help measure how an instrument responds to an analyte and how to estimate the concentration of an unknown sample. To build one, scientists prepare standard samples at several concentrations that include the expected range of the unknown. They then record the instrument response for each standard.

Transcript

校准曲线用于了解仪器对分析物的响应,并预测样品中分析物的浓度。

首先制备一组具有已知浓度分析物的标准溶液,从而创建校准曲线。测量每种溶液的仪器响应,并绘制与标准溶液浓度的关系图。然后,该图的线性部分可以通过将分析物样品的响应与浓度相关联来预测分析物样品的浓度。

本视频将介绍校准曲线及其应用,演示一组标准品的制备,然后分析浓度未知的样品。

使用一组标准溶液制备校准曲线。这些溶液由一系列浓度组成,这些浓度包括分析物的大致浓度。

标准溶液通常通过连续稀释制备。首先通过制备分析物的储备液进行连续稀释。然后将储备液稀释已知量,通常为一个数量级。然后以相同的方式稀释新溶液,依此类推。这会产生一组浓度在几个数量级之间的溶液。

校准曲线是仪器...

Tags

Calibration CurveSerial DilutionStandard SolutionInstrumental ResponseLinear RegressionLimit Of DetectionLimit Of QuantitationUV Vis SpectrophotometerStandard AdditionIon Selective Electrode

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