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00:00Black fire is one of the rarest and most intriguing phenomena on Earth.
00:04This flame has a unique characteristic.
00:06It absorbs light, creating an appearance similar to a black hole.
00:10To generate this flame, you need a flammable liquid like alcohol,
00:14which burns with a nearly transparent blue flame.
00:17Adding a saline solution changes the flame to a yellow hue.
00:20This occurs because the sodium atoms in the salt lose an electron and emit yellow light,
00:25similar to the principle used in old sodium vapor street lamps.
00:29When this flame is illuminated with a sodium vapor lamp,
00:32the sodium atoms in the flame absorb the light emitted by the lamp.
00:36This causes the flame to appear as if it is absorbing the light, turning black.
00:41This phenomenon happens because both the lamp and the flame emit light at the same frequency,
00:47causing the electrons in the flame to reabsorb the light and return to their ground state.
00:52Despite its dark appearance, black fire is not cold.
00:56It retains its normal temperature and combustible properties.
00:59This fascinating effect is an impressive illustration
01:02of how light absorption and emission work on an atomic level.