# Application of Statistical Concepts in the Determination of Weight Variation in Samples

Pages: 4 (1067 words) Published: April 28, 2013
DATE SUBMITTED: April 23, 2013
APPLICATION OF STATISTICAL CONCEPTS IN THE DETERMINATION OF WEIGHT VARIATION IN SAMPLES

P.C.Nicolas
Department of Chemical Engineering, College of Engineering, University of the Philippines Diliman Date Performed: April 19, 2013
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I. Results and Discussions
This experiment was aimed so that the students would be able to use the analytical balance properly, to be able to gain an understanding of some statistical concepts and be able to use these concepts in analytical chemistry. Analytical Chemistry focuses on the quantitative properties of matter specifically the inorganic compounds. Moreover, this experiment granted the students an overview of the subject.

In the experiment, ten 25c coin samples were weighed using the analytical balance. Forceps were used to handle the coins to ensure that the coin samples will not be tampered with fingerprints that may add to the weight of the samples. The recorded data were divided into two data sets. One data set contains the first six recorded data while the other contains all the 10 recorded values. The recorded data was shown in Table 1.

Table 1. Weight of the Samples
Sample Number| Weight in g|
1| 3.6430|
2| 3.6105|
3| 3.5957|
4| 3.6124|
5| 3.5555|
6| 3.5820|
7| 3.6020|
8| 3.6357|
9| 3.5839|
10| 3.5924|
For each data set, Q-test was used for the highest and lowest value. At 95% confidence level, it was found out that the extreme values for the two data sets are accepted and not an outlier. Calculations for the Q-test can be found in the attached data sheet. Q-test is used for handling rejection of data especially when dealing with small scale observations.

Data recorded in Table 1 were subjected to Measures of Central Tendency, Measures of Precision, and confidence limit aside from the Q-test.
Measures of Central tendency helps researchers...