Incredible Chemical Reactions

BELLOUSOV-ZHABOTINSKY REACTION

  • Named after Russian chemists.

  • Involves ferroin (iron atoms).

  • This changes according to the attached molecules, along with bromine and oxygen.

  • Reversible reaction: products revert back to reactants.

  • Reaction waves propagate, oscillating between red and blue states, requiring 18 reactions to complete the cycle.

LUMINOL

  • Molecule that emits light upon reacting with chemicals such as hydrogen peroxide.

  • Hydrogen peroxide steals hydrogen atoms from luminol, causing the formation of an unstable molecule.

  • This regression to a stable state produces visible light.

  • Needs a catalyst, such as iron, to react.

  • Used by investigators at crime scenes to detect blood, creating a faint glow where there are remnants.

SULFURIC ACID AND SUGAR

  • Structure of sugar: cycles of carbon, oxygen, and hydrogen atoms.

  • Sulfuric acid expels oxygen and hydrogen from sugar, leaving exposed carbon.

  • This creates a solid mass of graphite and releases sulfur dioxide, a toxic gas, requiring this reaction to be carried out in a laboratory.

THERMITE

  • The reaction between aluminum and iron oxide produces smoke and sparks.

  • Mixture of powdered iron oxide and aluminum ignited with a magnesium strip at high temperature (5,300 °F or 3,000 °C).

  • Iron loses its oxygen atoms, and aluminum captures them, forming molten iron.

  • Used for welding, particularly in rail track treatments and underwater welding.

BRIGGS-RAUSCHER REACTION

  • Also called oscillating reaction, involves iodine.

  • Oscillation of two colorless solutions to yellow and blue, depending on forms of iodine.

  • Produces a range of colors depending on the concentration of molecular and free iodine.

  • Stimulation of the solution causes rapid changes, while a lack of stimulus generates wave patterns similar to the Belousov-Zhabotinsky reaction.

ELEPHANT TOOTHPASTE

  • Produces a column of foam from soap, colored with food dye.

  • Involves hydrogen peroxide and a catalyst.

  • Rapid decomposition of hydrogen peroxide generates water and a lot of oxygen, creating millions of bubbles that form the foam.

DISPLACEMENT REACTION

  • Involves a bar of iron in copper sulfate.

  • When the sulfate dissolves, positively charged copper atoms are neutralized by iron atoms transferring electrons to them.

  • These neutralized copper atoms precipitate, creating a visible cloud of copper in the solution.

GUMMY BEARS EXPERIMENT

  • Heating potassium chlorate generates oxygen, and when a gummy bear is added, combustion occurs.

  • The reaction produces intense light and heat, resembling a campfire.

GOLDEN RAIN

  • The precipitation of lead iodide crystals is called "golden rain."

  • Two compounds, lead nitrate and potassium iodide, react to form a solid that escapes from the solution.

PHARAOH'S SERPENT

  • Produced by igniting mercuric thiocyanate.

  • Results in a column of ash that rises when burned.

  • The reaction is simple, but the material and gases are hazardous, previously considered safe for children.