Description: Balls in plastic bags represent atoms in molecules. Shuffling balls into different bags represent a reaction. The number and color of the balls does not change.

Concept: The atoms in a chemical reaction are conserved and chemical equations can be balanced.

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Description: Four balloons are filled with gas mixtures of CH4 and O2: one with pure O2, one with pure CH4, one with 2 CH4 / O2, and one with 1 CH4 / 2 O2. They are successively ignited with a burner. Only the balloon with the correct stoichiometric mixture will detonate.

Concept: CH4 is a flammable. The combustion reaction efficiency of CH4 and O2 depends on stoichiometry. Also, this reaction is slow at room temperature. The heat of the flame speeds up this reaction.

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Description: A bottle has two nails poking inside such that the points of the nails almost touch. A couple mL of methanol are put in the bottle and the bottle is corked and gently shaken and then clamped to a ring stand. A tesla coil is applied to the head of one of the nails. Almost immediately the methanol is ignited and the cork is shot into the air. Quickly the instructor corks the bottle. The bottle is shaken and the tesla coil is applied, but nothing happens. Why not? Then the instructor blows into the bottle, shakes, and uses the tesla coil to once again shoot the cork. Why does it work again?

Concept: Oxygen is required for the combustion of methanol. Also molecules in the vapor phase are farther apart than in the liquid phase and present more surface area for reaction.

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Description: A candle in lit and a jar is placed over it. Within a couple minutes the flame will extinguish due to lack of oxygen (the limiting reagent in this case).

Concept: A limiting reagent is defined as a reagent that will completely halt a reaction when it runs out.

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Description: One kilogram and 100 g samples are displayed to compare their sizes. A liter beaker is displayed to show its size. One mole samples of various elements and compounds are displayed. One mole of NaCl and 1 Liter beaker are shown in relationship together to demonstrate molarity.

Concept: A mole is not a measurement of a static amount of material.

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Description: A few students are given a piece of Bazooka bubble gum that has been pre-weighed and asked to chew the gum for about 20 minutes. After 20 minutes the pieces of gum are weighed again.

Concept: The molar mass (molecular weight) of sugar (sucrose) is large, 342.30 g/mol.

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Description: This demonstration is performed with the blue and white balls that contain Velcro. The machine is set up to contain the blue and white balls on opposite sides of the divider that contains a hole in the middle. The two blowers are set to push the blue and white reactant molecules into the gas phase. The hole in the divider represents the activation energy necessary for a reaction to occur.

Concept: Not only do reactant molecules have to collide with enough energy, but they must also collide with the correct orientation.

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