Today's class was called You Can't Spell Chemistry Without CSI! The teacher was Phil Cook, the TikTok chemistry teacher again.
He said that there was a crime that happened in his class and we were going to use chemistry to solve the case.
Here's the crime scene.
We can't guess what happened. We need to use the evidence to help us figure out what happened. Our first test was with a chemical called luminol. He showed how different materials react to it. Detectives often use it to see if there was blood at the scene of a crime.
At our crime scene, we found a handprint that reacted to luminol.
But he said this is a "presumptive test." He said it doesn't necessarily mean it's blood. There are other possibilities as well, like bleach or copper sulfate.
Next we collected fingerprints. We usually think of getting fingerprints by dusting but he used a method called iodine fuming.
This is the explanation of how it works.
Next we tested for gunshot residue. There were two types of tests that he did and both came up positive. But he said it just shows that a chemical was there, not where it came from.
The last thing we did was use flourescence and UV light. He said this last test showed that there was acetaminophen (pain medication) at the scene.
From this section, I also learned that UV light can show things your eyes can't see. So when someone tried to clean a scene with something like clorox wipes they won't necessarily catch everything since they can't see it.
So based on the evidence, he thinks it was a prank that his co-workers did on him. But he doesn't know for sure. He said you always have to have your critical thinking cap on and you need a lot of evidence to get the whole picture.
Here's a link to the recording of the class.
Comentarios