Luminol is a highly sensitive chemical test for what substance that produces a chemiluminescence of fifteen minutes duration or more?

Luminol is primarily used in forensic investigations to detect the presence of blood. When luminol comes into contact with hemoglobin, a component of red blood cells, it undergoes a chemical reaction that produces light, a process known as chemiluminescence. This reaction is highly sensitive and can indicate the presence of blood even when it has been cleaned or diluted. The resulting glow can last for approximately fifteen minutes or more, allowing investigators time to document and analyze the evidence.

The context in which luminol is used emphasizes its effectiveness in detecting blood at crime scenes, particularly when it is crucial to establish whether blood is present, often leading to further investigations. Other substances listed, like water, oil, or salt, do not produce the same reaction with luminol and do not serve as indicators of blood in forensic science. Thus, the ability of luminol to specifically signal the presence of blood makes it an invaluable tool in crime scene analysis.