Analytical Chemistry Chapter 0

Analytical Chemistry

uses methods and instruments to separate, identify, and quantify matter

Classical Wet Methods

• Precipitation (formation of a solid)

• Extraction

• Distillation

Identify by:

• Color

• Odor

• Melting Point

• Boiling Point

• Solubility

• Radioactivity

• Reactivity

Instrumental Methods

• Heat: Thermochemistry

• Electric: Electrochemistry

• Magnetic Fields: NMR

• Light: Spectroscopy

Heterogeneous

Varies throughout

Homogeneous

Same throughout

What is present?

Qualitative Analysis

How much is present?

Quantitative Analysis

Sample Preperationg

Transforming a sample into a state suitable for analysis

Analyte

Species being measured

Aqueous

In water

Slurry

Suspension of solid in liquid

Supernatant liquid

Liquid above the solid in a settled solution

Quantitative transfer

Get it all

Centrifugation

spin to separate species of differing mass

Decant

Pour off the liquid only

Extraction

separation based on solubility

Distillation

Based on volatility (boiling point)

Filtration

Based on size

Interference

Species other than the analyte that affects the result

Masking

Transformation of interfering species into a form that does not cause problems

Aliquot

Identical portions