Ch.3 - Experimental ErrorWorksheetSee all chapters
All Chapters
Ch.1 - Chemical Measurements
Ch.2 - Tools of the Trade
Ch.3 - Experimental Error
Ch.4 + 5 - Statistics, Quality Assurance and Calibration Methods
Ch.6 - Chemical Equilibrium
Ch.7 - Activity and the Systematic Treatment of Equilibrium
Ch.8 - Monoprotic Acid-Base Equilibria
Ch.9 - Polyprotic Acid-Base Equilibria
Ch.10 - Acid-Base Titrations
Ch.11 - EDTA Titrations
Ch.12 - Advanced Topics in Equilibrium
Ch.13 - Fundamentals of Electrochemistry
Ch.14 - Electrodes and Potentiometry
Ch.15 - Redox Titrations
Ch.16 - Electroanalytical Techniques
Ch.17 - Fundamentals of Spectrophotometry
BONUS: Chemical Kinetics
Sections
Significant Figures
Addition and Subtraction Operations
Multiplication and Division Operations
Logarithm and Anti-Logarithm Operations
Precision and Accuracy
Types of Errors
Uncertainty
Propagation of Uncertainty: Triangular Distribution

All calculations are associated with some level of uncertainty which we define as its error

Types of Errors

Concept #1: Error can be categorized as either systematic or random

Example #1: A uncalibrated pipet is used in the titration of 25 mL of 0.250 M KMnO4 with 50.0 mL of HNO3. If the pipet delivers 23.120 +/- 0.02 mL what can be said about the possible error(s) observed? 

Example #2: State whether the errors are random or systematic for each of the following:

a)  The analytical measuring pipet in the lab consistently delivers 25.0   0.03 mL.

 

b)  I weigh an analyte sample 4 times and obtain the following numbers: 1.110, 1.392, 1.040 and 1.850.