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If ion spectrometry results showed positive for presence of a substance is it possible that it is wrong?
Ion Spectrometry can be highly inaccurate. False alarms can be made due to the detectors inability to differentiate between some other substance and the one looked for. This may have to do with whether or not the false positive has been programed into the detector - in order to weed it out.
NOTE: It's not really that ion spectrometry is inaccurate. It is extremely accurate. Where there is A LOT of room for mistake is in the interpretation of the data. The detector doesn't identify anything. It simply sees a signal at a certain charge to mass ratio. The mistake is human error (unless the machine isn't working properly of course). Ion spectrometry can easily distinguish two molecules that differ by only one atom.
Ion spectrometry works essentially by weighing the mass of the components of a mixture. You then use the mass to match with what you think might be in the sample. Here is where the mistakes happen.
Here is an analogy: You've been robbed, and somehow you know the exact weight of the perpetrator. The police arrest somebody and he happens to weigh the same amount as the person that robbed you. Does that make the person guilty? No! There are lots of people that weigh the same amount as each other. Does it mean the scale that weighed the person was wrong or inaccurate? No!
Determining somethings identity by its mass is risky unless you have other knowledge about what you think it is. Just like in my analogy. If you knew the robber's weight and also that he had gray hair and blue eyes and was wearing a purple hat, then if the guy the police caught matched ALL of those details, you'd be pretty sure you got the right guy. But by weight alone, it can lead to mistakes.
What else can I help you with?
What does a positive Molisch's test on an unknown substance indicate?
A positive Molisch's test result indicates the presence of carbohydrates.
How is it possible to detect polonium in tobacco?
Polonium can be detected in tobacco samples using analytical techniques such as alpha spectroscopy, mass spectrometry, or gamma spectroscopy. These methods can quantify the concentration of polonium in the tobacco and help researchers understand the extent of its presence.
What is positive color for iodine test?
The positive color for the iodine test is a dark blue or black color. This color change indicates the presence of starch in the test substance.
Name two confirmatory tests for the presence of intact explosives located in debris?
Two confirmatory tests for the presence of intact explosives in debris are gas chromatography-mass spectrometry (GC-MS) and ion mobility spectrometry (IMS). These tests can provide specific molecular information about the components of the explosive material present in the debris.
What can you use to detect depleted uranium?
Geiger-Muller counters, inductively coupled plasma mass spectrometry (ICP-MS), and alpha spectrometry are commonly used to detect depleted uranium due to their ability to measure radiation levels and isotopic composition. Environmental sampling and laboratory analysis are typically required to confirm the presence of depleted uranium in a given sample.
Does the presence of hydrogen bonding in a substance imply the presence of dipole-dipole interactions as well?
Yes, the presence of hydrogen bonding in a substance implies the presence of dipole-dipole interactions as well.
How can sulfur be effectively removed from a substance or environment?
Sulfur can be effectively removed from a substance or environment through processes such as chemical precipitation, oxidation, or filtration. These methods help to separate sulfur from the substance or environment, making it possible to reduce or eliminate its presence.
Benedict's turns orange when heated in the presence of a?
reducing sugar. Benedict's reagent is a solution used to test for the presence of reducing sugars, which includes glucose and fructose. The color change to orange indicates a positive result for the presence of reducing sugars in the substance being tested.
How do you tell if a substance contains protein by using biuret test?
If Biuret Reagent is related to the presence of Protein macromolecules, then a positive result will change it's colour from blue to violet.
Why does resorcinol give a false positive with the Duquenois Levine test?
Resorcinol can interfere with the Duquenois-Levine test by producing a similar color change as THC when exposed to the test reagents. This can lead to a false positive result for THC in the presence of resorcinol.
What group of substance that give positive reaction to molisch test?
Carbohydrates typically give a positive reaction to the Molisch test. This is because the Molisch reagent reacts with the carbohydrates to form a purple complex, indicating the presence of sugar molecules in the solution.
What is the burning of a substance in the presence of oxygen?
combustion
