CHEM 130 Lecture Notes - Lecture 2: Significant Figures, Decimal Mark, Ampere
Document Summary
Chem 130: general chemistry: macroscopic investigations and reaction principles - Comparison of a physical quantity to be measured with a fixed standard of measurement. The closeness of the set of values obtained from identical measurement of a quantity. The closeness of a single measurement to its true value. Digits in a measured number that include all certain digits plus a final digit having some uncertainty. Used to indicate the precision of a measured number. A ruler will tell you a metal rod is exactly 9. 1cm. You can estimate that the rod may be 9. 12cm or 9. 13cm. The first two digits are certain (the rod is definitely at least 9. 1cm) but the digit is not (you don"t know if it 9. 12cm or. Additionally, you cannot write 9. 120 because that would mean the last digit (0) is uncertain and the other digits (9. 12) are certain, which is not true.
