Page 6 - Vogel's TEXTBOOK OF QUANTITATIVE CHEMICAL ANALYSIS

CONTENTS

3.20 Meta1 apparatus 93
3.21 Heating apparatus 97
3.22 Desiccators and dry boxes 98
3.23 Stirring apparatus 101
3.24 Filtration apparatus 102
3.25 Weighing bottles 104
REAGENTS AND STANDARD SOLUTIONS
3.26 Reagents 104
3.27 Purification of substances 105
3.28 Preparation and storage of standard solutions 107
SOME BASIC TECHNIQUES
3.29 Preparation of the substance for analysis 109
3.30 Weighing the sample 110
3.31 Solution of the sample 110
3.32 Precipitation 1 15
3.33 Filtration 115
3.34 Filter papers 115
3.35 Crucibles with permanent porous plates 117
3.36 Washing precipitates 1 18
3.37 Drying and igniting precipitates 119
3.38 References for Part A 122
3.39 Selected bibliography for Part A 122

PART B ERRORS, STATISTICS, AND SAMPLING

CHAPTER 4 ERRORS AND STATISTICS

4.1 Limitations of analytical methods 127
4.2 Classification of errors 127
4.3 Accuracy 128
4.4 Precision 129
4.5 Minimisation of errors 131
4.6 Significant figures and computations 132
4.7 The use of calculators and microcomputers 133
4.8 Mean and standard deviation 134
4.9 Distribution of random errors 136
4.10 Reliability of results 137
4.1 1 Confidence interval 138
4.12 Comparison of results 139
4.13 Comparison of the means of two samples 140
4.14 Paired t-test 142
4.15 The number of replicate determinations 142
4.16 Correlation and regression 144
4.17 Linear regression 145
4.18 Comparison of more than two means (analysis of variance) 146
4.19 The value of statistics 149

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