Define a pure substance.
Composed of a single type of atom or molecule (e.g., Au, H₂O).
Define a mixture.
Composed of two or more elements or compounds physically combined.
Define a homogeneous mixture.
A mixture with uniform composition; individual components are not visible.
Define a heterogeneous mixture.
A mixture with non-uniform composition; different components are visible.
Define distillation.
Separation of liquid mixtures based on differences in boiling points.
Define filtration.
Separation of solids from liquids using a filter.
Define Thin-Layer Chromatography (TLC).
Separation of mixtures based on attraction to solids/liquids or polarity differences.
Define Retention Factor ($R_f$) in TLC.
Ratio of the distance traveled by the component to the distance traveled by the solvent: $R_f = \frac{\text{distance traveled by the component}}{\text{distance traveled by the solvent}}$
What are the general steps of distillation?
1. Heat the liquid mixture. 2. The substance with the lowest boiling point evaporates. 3. Vapor is cooled and condenses. 4. Collect the separated liquid.
What are the steps of filtration?
1. Prepare the filter. 2. Pour the mixture through the filter. 3. Liquid passes through. 4. Solid remains on the filter.
Outline the general steps of Thin-Layer Chromatography (TLC).
1. Spot the sample on the TLC plate. 2. Place the plate in a solvent. 3. Solvent moves up the plate by capillary action. 4. Components separate based on polarity. 5. Visualize the separated components.
What is the effect of a lower boiling point in distillation?
The substance evaporates first and is separated from the mixture.
What is the effect of a substance being insoluble in a solvent during filtration?
The substance is trapped by the filter paper.
What is the effect of high polarity on a compound in TLC with a nonpolar solvent?
The compound moves a shorter distance on the TLC plate.
