Elements and Periodic Table Demonstrations

See also: Atoms

Elements are pure substances made up of only one type of atom. The periodic table organises these elements to reveal patterns in their properties and behaviours. This category introduces the significance of the table, the families and groups within it, and the insights it offers for predicting chemical behaviour.

Demonstration	Materials	Difficulty	Safety	Summary
Gallium and Aluminium Can	★★★	★☆☆	★★☆	When liquid gallium is applied to an aluminum can, it penetrates the aluminum’s grain boundaries and disrupts its crystal structure, making the can brittle and easy to puncture.
Iron in Cereal	★☆☆	★☆☆	★☆☆	Blend cereal with water to make a slurry, then pass it by a strong magnet to collect supplemental iron particles.
Melting Gallium in Your Hand	★★★	★☆☆	★★☆	Gallium, a metal with a melting point of 29.76 °C (85.6 °F), can melt in the palm of your hand. The demonstration shows how body heat is enough to turn solid gallium into a silvery liquid.
Preparing and Testing Hydrogen Gas	★★☆	★☆☆	★★☆	Hydrogen gas is produced when zinc reacts with hydrochloric acid. The gas is collected over water and tested with a lit splint, which produces a distinctive ‘pop’ sound, confirming the presence of hydrogen.
Preparing and Testing Oxygen	★★☆	★☆☆	★★☆	Oxygen can be produced by decomposing hydrogen peroxide. The reaction is sped up by a manganese(IV) oxide catalyst. The gas can be tested with a glowing splint, which relights in oxygen.
Allotropes of Sulfur	★★☆	★★☆	★★☆	When powdered sulfur is heated, it undergoes a series of changes in appearance and physical properties. Sulfur melts, becomes highly viscous as polymer chains form, then flows more freely at higher temperatures before eventually igniting. Quenching burning liquid sulfur in water produces a flexible, rubbery form of sulfur.
Burning Magnesium Ribbon	★★☆	★★☆	★★☆	A strip of magnesium ribbon, when ignited, burns with an intense white flame, producing magnesium oxide. The reaction is highly exothermic and demonstrates how metals can react vigorously with oxygen.
Flame Tests	★★☆	★★☆	★★☆	Different metal ions produce characteristic flame colors when their solutions are heated in a flame.
Genie in a Bottle	★★☆	★★☆	★★★	When manganese dioxide is added to concentrated hydrogen peroxide, it rapidly decomposes into water and oxygen gas. The escaping oxygen propels a mist of water out of the container, creating the dramatic effect of a “genie” emerging from the bottle.
Hydrogen Balloon Explosion	★★★	★★☆	★★★	A helium-filled balloon and a hydrogen-filled balloon are ignited to compare their reactions. The helium balloon produces no reaction, while the hydrogen balloon explodes with a loud sound and flame, illustrating combustion and the differences in gas properties.
Making Chlorine Gas	★★☆	★★☆	★★★	Chlorine gas, a pale greenish-yellow substance, can be produced by reacting potassium permanganate with concentrated hydrochloric acid.
Methanol Flame Colors	★★☆	★★☆	★★☆	Metal salts are heated in burning methanol to produce vivid flame colors that correspond to electronic transitions in their ions.
Sugar and Sulfuric Acid Carbon Snake	★★☆	★★☆	★★☆	Concentrated sulfuric acid is added to sugar, causing a vigorous dehydration and oxidation reaction. The mixture heats up and produces steam, carbon dioxide, and a growing black column of carbon that resembles a snake rising from the container.
Vanadium Oxidation States	★★★	★★☆	★★☆	This experiment demonstrates the multiple oxidation states of vanadium by producing vivid colors (yellow, green, blue, dark-green, and purple) in a single solution. Starting from vanadium pentoxide, vanadium compounds are reduced with zinc and then re-oxidized with potassium permanganate, creating a reversible rainbow of colors.
Sodium in Water	★★★	★★★	★★★	A pea-sized piece of sodium metal is placed on water, where it reacts exothermically to form sodium hydroxide and hydrogen gas. Heat from the reaction can ignite the hydrogen, and a pH indicator shows the solution becoming alkaline.
Sodium in Water Explosion	★★★	★★★	★★★	A large chunk of sodium metal is added to a plastic bowl of water, it catches fire the explodes.

Materials
★☆☆ Easy to get from supermarket or hardware store
★★☆ Available in most school laboratories or specialist stores
★★★ Requires materials not commonly found in school laboratories

Difficulty
★☆☆ Can be easily done by most teenagers
★★☆ Available in most school laboratories or specialist stores
★★★ Requires a more experienced teacher

Safety
★☆☆ Minimal safety procedures required
★★☆ Some safety precautions required to perform safely
★★★ Only to be attempted with adequate safety procedures and trained staff