Laboratory Techniques in Organic Chemistry
4th Edition
ISBN: 9781464134227
Author: Jerry R. Mohrig, David Alberg, Gretchen Hofmeister, Paul F. Schatz, Christina Noring Hammond
Publisher: W. H. Freeman
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Question
Chapter 5, Problem 8Q
Interpretation Introduction
Interpretation:
The average value and the uncertainty by the use of standard deviation of given data should be determined.
Concept introduction:
Each of the digits of a number that is utilized to express it to the needed degree of accuracy from the initial first non-zero digit is known as a significant figure. The rightmost digit of the quantity is the most uncertain digit. The number of certain and uncertain digit in a quantity is considered as significant figures. The digit with a higher number of significant figures has a higher certainty of measurement.
The rules for the significant figures are as follows:
- All non-zero digits are generally considered significant.
- Zeros are present between two digits that are non-zero are always significant.
- Zeros present to the left of the significant figures are not significant.
- Trailing zeroes that do are used to set a decimal point are non-significant figures.
Rules to calculate the significant figures in calculations are as follows:
- In addition and subtraction operations, the result carries same number of decimal places as the operand or measurement with fewest decimal places.
- In multiplication and division operations the result carries same number of significant figures as the operand or measurement with the fewest significant figures. While the exact numbers have no affect on number of significant digits in the final answer.
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Chapter 5 Solutions
Laboratory Techniques in Organic Chemistry
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