?????? Geo-analytical Chemistry

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?????? Geo-analytical Chemistry ???
Chuan-Chou (River) SHEN river_at_ntu.edu.tw Course
Description This course is intended for
graduate students in the Dept. of Geosciences,
without an extensive background in chemistry. It
emphasizes both theoretical and practical aspects
of analytical techniques for geochemical
research. Modern instrumental techniques and
experimental methods will be included. Paper
reading, discussion and presentation will also
play essential roles in class. After taking this
class, students will be able to design an overall
experimental procedure, including estimating
sample size, sampling, choosing chemicals and
labwares and selecting measurement methods for
their projects. They will also learn how to
independently accomplish chemistry in a
geochemical lab.
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Literature Quantitative Chemical Analysis by
Daniel C. Harris Fundamentals of Analytical
Chemistry by Skoog and West Statistics for
Analytical Chemistry by Miller and
Miller Data Reduction and Error Analysis for the
Physical Sciences
by Bevington and
Robinson Text materials Selected chapters,
class handouts, papers. Credits 2 Class hours
700-900 pm, Thursday Grading Homework, 10
Midterm exam, 30 Report and presentation,
20 Final, 40.
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Syllabus Sept Introduction, Uncertainty,
Probability, distributions. Oct Error
analysis. Significance tests. Regressi
on correlation. Methods for quantitative
analysis. Nov Geochem lab labwares, clean
room, QA/QC. Geochem lab acids, standards,
spikes, safety rule. Samples and
sampling. Nov 27 Midterm exam. Dec Dissolution
and separation techniques. Ion exchange
chromatography. Analytical methods for
geo-environmental samples. Dec 18 2003 AGU Fall
Meeting. Jan Paper discussion. Geo-analytical
techs. Analytical methods for
geo-environmental samples. Jan 15 Final oral
exam.
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• Introduction
• 1.1. Types of geochemical surveys
• a. Rock surveys
• b. Sediment and soil surveys
• c. Stream, lake and ocean water surveys
• d. Vegetation (biogeochemical) surveys
• e. Gas surveys

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• Increased availability of toxic Al3 to a pine
  tree in Germany near a coal-burning power plant
  built in 1929. The increase is probably an effect
  of man-made acidity in rainfall, which mobilizes
  Al3 from minerals.
• The growth of atmospheric CO2. CO2 comes from our
  burning of fossil fuel and destruction of
  forests.
• The growth in world population.
• How long will our planet remain habitable if we
  do not control our population and our impact on
  the environment?

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• 2. Uncertainties in measurements
• 2.1. Analytical problems qualitative
• Does this distilled water sample contain any
  boron?
• Could these two igneous rock samples have come
  from the same site?
• How much lead is there in this sample of
  tap-water?

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2.2. Answers quantitative I can/cannot detect
boron in this water sample. A quantitative method
capable of detecting boron at levels of 1
mg/ml This sample contains lt 1 mg/ml boron
(detection limit). This sample contains gt 1
mg/ml boron (e.g. 1.4 mg/ml) (1.4 1.2 mg/ml
1.4 0.2 mg/ml 1.40 0.02 mg/ml).
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2.3. Types of error 2.3.1. Gross error (gross
mistake) reversing a sign, using a wrong scale,
arithmetic mistakes 2.3.2. Determinate error
(systematic error) a. Instrument errors b.
Method errors c. Personal errors Constant vs.
Proportional
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The accuracy of an experiment is dependent on how
well we can control or compensate for systematic
errors. Systematic errors affect accuracy, i.e.
proximity to the true value. Errors make results
different from the true values with reproducible
discrepancies. How to reduce systematic errors?
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2.3.3. Indeterminate error (random
error) Indeterminate error arises from
uncertainties in a measurement that are unknown
and not controlled by the scientist (operator).
The precision of an experiment is dependent on
how well we can overcome random errors. Random
errors affect precision, or reproducibility, of
an experiment. To reduce random errors
a. Repeating the experiment b.
Improving the experimental method c.
Refining the techniques Repeatability within-run
precision Reproducibility between-run precision
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Repeatability within-run precision Reproduci
bility between-run precision
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