仪器分析作业¶
Homework 1¶
Analytical Chemsitry for Technicians 1.7¶
Errors
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Determinate Errors (AKA Systematic Errors) 相当于"已经找到原因的错误"
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Avoidable Errors (本)可以避免的错误 结果: 样本的弃用 / 重新计算(recalculate)
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Unavoidable Errors 结果: 由于已经确定, 然而不可避免, 也就是说这样的错误 总是 出现, 因此我们知道这个错误的效果, 也可以修正(apply a correction factor)
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Indeterminate Errors (AKA Random Errors)
Cite
..., a statistical analysis must be performed to determine whether the results are far enough "off-track" to merit rejection.
Standard deviation
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N: the number of measurements
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N-1: the number of degrees of freedom
Cite
An infinite number of measurements is apporximated by 30+ measurements.
Normal Distribution
Cite
The curve is called the normal distribution curve because it represeents a normal distribution of values for any infinitely related measurement.
Question
Why?
Precision vs. Accuracy
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Precision: "the measurements deviate how slightly from one anothers", 相互之间的差距, 但可能整体都"跑偏"真实值
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Accuracy: "how close it comes to the correct value of a paramter"
Words&Phrases
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population 总体的
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jeopardy 危险境地
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calibrated 被校准的 -> calibration 校准; 标准化
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reagent impurities 反应物不纯
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give rise to 产生
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dispersion 离差
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yield 出产; 屈服; 放弃
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foregoing = previous mentioned 之前提到的
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consecutive 连续的 = continuous
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designate 指派, 委派 = assign
电化学科学 Page 25-40¶
电化学可定义为研究一个传导电子的导电相(通常是金属), 与一个离子导电相(通常是一个水溶液)之间的界面上所发生的的界面效应的科学.
- 能斯特方程式, 是来源于电子传递反应的逆向反应与正向反应速度的量子力学方程式: