chapter 0: the analytical process...

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Chapter 0:The Analytical Process (Example)

1. Formulating the Question

2. Selecting Analytical Procedures

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3. Sampling

Random Heterogeneous Material

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Segregated Heterogeneous Material

4. Sample Preparation

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5. Analysis

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6. Reporting and Interpretation

7. Drawing Conclusions

Terminology to Know From the Example

representative sampling – random vs. segregated

sample preparation

extraction, centrifugation, filtering

chromatography, stationary phase, adsorption

aliquot

calibration curve

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Chapter 2:

Tools of the Trade

Mechanical Balance

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Electronic Balance

Buoyancy correction - a sample appears lighter than its actual mass by an amount equal to the mass of the air it displaces.

d

d

d

dm

ma

w

a

1

1'

Example: Find the true mass of water (density = 1.00 g/mL) if the apparent mass is 100.00g

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Calibration of Volumetric Glassware

True volume = mass H2O x correction factor

Example p. 49: an empty weighing bottle had a mass of 10.283 g. After water was added from a 25-mL pipet, the mass was 35.225 g. The temperature was 23oC. Find the volume of water delivered by the pipet.