Description: Several types and colors of markers are spotted onto chromatography paper and allowed to develop for 10-15 minutes in a chamber containing water as the mobile phase.

Concept: A mixture of chemicals can be separated based on their relative affinities for the chromatography paper and solvent.

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Description: A deep, yellow-green extract derived from raw spinach is eluted through a chromatography column containing silica. The result is a separation of the ?-carotene and chlorophyll pigments in the spinach. When completed, the students should be able to see distinct yellow and green bands in the column.

Concept: Molecules contained within a mixture can be separated based on their differing affinities for various solvents.

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Description: CaCl2 and Na2CO3 are weighed together before and after they are mixed to form a precipitate to show that mass is conserved.

Concept: The total mass of substances does not change during a chemical reaction. When one volume of liquid is mixed with another volume of liquid that is less dense than the first, the total volume of the two liquids will not be the sum of the two individual liquids. The molecules of one liquid can fill in the volume between the molecules of another.

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Description: Green food coloring (a mixture of food dyes Blue 1 and Yellow 5) is separated into its components using a C18 Sep Pak and various mixtures of methanol and water.

Concept: A nonpolar stationary phase is used for reverse-phase chromatography. The material contained in the Sep Pak cartridge is relatively nonpolar, and will retain other nonpolar molecules.

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Description: Total brand cereal is ground into a powder and stirred with a magnetic stir bar in water. Minutes later, the stir bar is pulled out to reveal iron filings that had been put into the cereal as a nutritional supplement. As an alternative demonstration, the ground cereal can be placed in a small vial suspended from a string. The iron in the cereal will cause the vial to be attracted to a gap magnet.

Concept: Iron metal is often added to breakfast cereals as a nutritional supplement. Since iron is paramagnetic, it will be attracted to a magnetic field.

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Description: Na and Mg metals react with oxygen to produce basic oxides that turn universal indicator purple (basic). Carbon on the other hand reacts with oxygen to produce an acidic oxide that turns universal indicator orange (acidic).

Concept: Most metals react with oxygen to produce basic oxides. Most non-metals react with oxygen to produce acidic oxides.

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Description: Lithium, sodium, and potassium metals are sliced and then a small sample of each is reacted with water.

Concept: The alkali metals are soft and silvery. They are also the most reactive metals having the lowest ionization energies. They react readily with water, lithium being the least reactive and potassium the most.

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Description: Samples of Mg and Ca are displayed. Mg and HCl produce less bubbles than Ca and HCl. Mg and H2O produces less hydroxide and therefore less pink with phenolphthalien than Ca and H2O.

Concept: The alkaline earth metals are less reactive and harder compared to the alkali metals. They do not react as readily with water. Mg is less reactive than Ca.

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Description: Many samples of elements are available to be displayed in class.

Concept: An element is a substance that cannot be decomposed by any chemical reaction into simpler substances; a type of matter composed of only one kind of atom, each atom of a given kind having the same properties.

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Description: Small cards showing each element and their atomic number are arranged to form the periodic table.

Concept: When the elements are arranged by atomic number, their physical and chemical properties such as atomic radius, ionization energy and electron affinity, vary periodically.

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Description: Several samples of alkanes are displayed.

Concept: The physical properties of the alkanes are related to their molecular structure.

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Description: Tollen's Reagent is added to two flasks. A dextrose water solution is added to one and swirled. The contents of the flask turn brown and then silver is plated onto the inside of the flask. Sucrose is added to the other flask. The contents may turn brown but no silver is plated.

Concept: Silver (I) is reduced to silver metal by aldehydes but not by ketones.

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