Purpose
To demonstrate the use of a chemical reaction and weighing
to determine the thickness of a thin coating of Zn on a steel washer.
To use statistical techniques to extract the maximum amount of information
out of a limited data set and calculate the inherent uncertainty
in the measurements.
Know Terms
Mixture vs Compound vs Element
Corrosion
Galvanization
Random error
Systematic error
Accuracy
Precision
Relative error
Absolute error
Know how to read a vernier caliper
Know Calculation of
Area of a circular object
mass from density
Statistical parameters: average, standard deviation
use of t-tables and calculation of confidence interval
The confidence interval for an experiment may be improved (narrowed) by
1. collecting more data-not very practical after 5-6 points
2. reducting the standard deviation-using better technique or equipment – this is the most efficient way