Chem 28.1 Rdr 2
Application of Statistical Concepts in the Determination of Weight Variation in Samples
Galingana, Cara Lois T.
Department of Food Science and Nutrition, College of Home Economics
University of the Philippines, Diliman, Quezon City
Date Due: December 7, 2012
Date Submitted: December 7, 2012
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Keywords: Sampling, Central Tendency, Accuracy, Precision, Quantity, Statistical Tests
RESULTS AND DISCUSSION
In the experiment, the class was able to use an analytical balance properly, gain an understanding of some concepts of statistical analysis, and apply statistical concepts in analytical chemistry.
The data was gathered using an electronic analytical balance. This equipment has a precision and accuracy that exceeds 1 part in 106 at full capacity. It can measure from 0.0001 mg to 30 g. The electronic analytical balance used in the lab features a taring control that disregards the weight of the container on the pan. Thus, the value displayed on the balance only refers to the sample in the container.
Ten 1-peso coins were then collected as samples. Each coin was weighed on the balance, showing variation in the data gathered.
Table 1.1 Weights of Ten 1-Peso Coins Measured on the Electronic Analytical Balance Sample No. | Weight, g | 1 | 5.3604 ± 0.0002 | 2 | 5.4112 ± 0.0000 | 3 | Data Set 1
Data Set 1
6.1109 ± 0.0001 | 4 | 5.3679 ± 0.0000 | 5 | Data Set 2
Data Set 2
5.4044 ± 0.0002 | 6 | 5.4066 ± 0.0000 | 7 | 5.3139 ± 0.0001 | 8 | 6.0423 ± 0.0000 | 9 | 5.3742 ± 0.0002 | 10 | 5.4798 ± 0.0001 |
The first 6 samples were grouped as Data Set 1, while all 10 samples were grouped as Data Set 2. These data sets were then used for statistical analysis.
The first statistical test done in the experiment is the mean. This test is a measure of central tendency, which is used as the average with interval or ratio data. It is considered to be the center of gravity of distribution,
Galingana, Cara Lois T.
Department of Food Science and Nutrition, College of Home Economics
University of the Philippines, Diliman, Quezon City
Date Due: December 7, 2012
Date Submitted: December 7, 2012
-------------------------------------------------
Keywords: Sampling, Central Tendency, Accuracy, Precision, Quantity, Statistical Tests
RESULTS AND DISCUSSION
In the experiment, the class was able to use an analytical balance properly, gain an understanding of some concepts of statistical analysis, and apply statistical concepts in analytical chemistry.
The data was gathered using an electronic analytical balance. This equipment has a precision and accuracy that exceeds 1 part in 106 at full capacity. It can measure from 0.0001 mg to 30 g. The electronic analytical balance used in the lab features a taring control that disregards the weight of the container on the pan. Thus, the value displayed on the balance only refers to the sample in the container.
Ten 1-peso coins were then collected as samples. Each coin was weighed on the balance, showing variation in the data gathered.
Table 1.1 Weights of Ten 1-Peso Coins Measured on the Electronic Analytical Balance Sample No. | Weight, g | 1 | 5.3604 ± 0.0002 | 2 | 5.4112 ± 0.0000 | 3 | Data Set 1
Data Set 1
6.1109 ± 0.0001 | 4 | 5.3679 ± 0.0000 | 5 | Data Set 2
Data Set 2
5.4044 ± 0.0002 | 6 | 5.4066 ± 0.0000 | 7 | 5.3139 ± 0.0001 | 8 | 6.0423 ± 0.0000 | 9 | 5.3742 ± 0.0002 | 10 | 5.4798 ± 0.0001 |
The first 6 samples were grouped as Data Set 1, while all 10 samples were grouped as Data Set 2. These data sets were then used for statistical analysis.
The first statistical test done in the experiment is the mean. This test is a measure of central tendency, which is used as the average with interval or ratio data. It is considered to be the center of gravity of distribution,
References: Downie, N.M.; Heath, R.W. Basic Statistical Methods, 5th ed.; New York, 1983 Siegel, A. F. Practical Business Statistics, 2nd ed.; Illinois, 1994 Skoog, D. A.; West, D. M.; Holler, F. J.; Crouch, S. R. Fundamentals of Analytical Chemistry, 8th ed.; Canada, 2004 Quantitative Inorganic Analysis Laboratory Manual, 2007 ed. Institute of Chemistry, UP Diliman, Quezon City