UNIT 4 LESSON 8 – CHEMICAL ANALYSIS

Pure Substances

Pure Substances

Single elements or compounds not mixed with any other substance, with specific melting and boiling temperatures for identification.

Formulations

Mixtures designed as useful products by combining components in measured quantities to achieve desired properties.

Chromatography

Technique to separate mixtures using a stationary and mobile phase, with Rf values to identify compounds based on their movement distances.

Test for Hydrogen

Involves a burning splint producing a pop sound when in contact with hydrogen gas.

Test for Oxygen

Uses a glowing splint that relights in the presence of oxygen gas.

Test for Carbon Dioxide

Involves using limewater that turns milky when shaken with carbon dioxide gas.

Test for Chlorine

Damp litmus paper bleaches and turns white when exposed to chlorine gas.

Flame Tests

Method to identify metal ions by observing the distinctive colors they emit when burned in a flame.

Metal Hydroxides

Sodium hydroxide solution forms colored precipitates with certain metal ions, aiding in their identification.

Identifying Carbonates

Carbonates react with acids to produce carbon dioxide, which can be detected with limewater.

Identifying Halide Ions

Halide ions form characteristic precipitates with silver nitrate, helping in their identification.

Identifying Sulfate Ions

Sulfate ions produce a white precipitate with barium chloride, indicating their presence.

Instrumental Methods

Accurate, sensitive, and rapid techniques to detect and identify elements and compounds.

Flame Emission Spectroscopy

Analytical method using a flame to produce light for identifying metal ions in solution through a line spectrum analysis.