RHYS LEWIS, AHS, DECD, UNISA / EQUINOX GRAPHICS / SCIENCE PHOTO LIBRARY RHYS LEWIS, AHS, DECD, UNISA / EQUINOX GRAPHICS / SCIENCE PHOTO LIBRARY
Animation of an experiment showing the electrolysis of water into its constituent parts, hydrogen and oxygen. The apparatus comprises two platinum electrodes either side of a reservoir of water. Electricity is passed through the circuit. In the first inset, at the negatively charged cathode, electrons (blue) are donated to water molecules, splitting them into hydroxide ions (OH-) and hydrogen gas. The second inset shows water at the positive anode, which accepts electrons from the water, splitting the molecules and forming oxygen gas. Twice as much hydrogen as oxygen is produced, as there are twice as many hydrogen atoms in a water molecule (H2O). The gases are both tested in boiling tubes filled by opening taps at the vessels' tops. When a lit splint is placed in hydrogen gas, it explodes with a characteristic squeaky pop. When a glowing splint is placed in oxygen, it relights.
Model release not required. Property release not required.