The gas iodine will stick to the fingerprints because they will crystallize when they come into contact with a cool surface. When heated, iodine directly changes into vapor.
Solid iodine sublimes, meaning it transitions directly from a solid to a gas without becoming a liquid. This property makes it difficult for iodine to leave residue on fingers when touched, which is why it doesn't stick to fingerprints.
because when they are heated they are sticky and they only fix to fingers
iodine is a covalent compound and no ionic properties. there are no free electrons on it. so it can not conduct electricity.
Solid iodine sublimes at room temperature, meaning it goes directly from a solid to a gas without melting. As a result, it does not stick to surfaces like fingerprints because it does not become liquid when in contact with the skin. When heated, the iodine turns into a gas, which can then interact with the oils and sweat in the fingerprint, making it visible.
because the iodine needs to make contact with the fingerprint so when it's a solid it can't do that. However when it is heated it turns in to gas (sublimation) it rises up and as it make contact with a coooler surface (the fingerprint) it crystallizes and makes it visable.
dont now
probably because iodine sticks to the oil from your fingers
It is simple
no there is not a better substance
yes,yes there is
my head
It has been used as a method to develop latent fingerprints on items of evidence. The fingerprints must be photographed as their visibility does not last. Iodine has been used when the evidence must not appear to have been examined, such as mail fraud cases where the fingerprints are developed and then the mail continues on it's way to allow authorities to trap the accomplice.