Chemicals And Powders Flashcards
1
Q
Describe the Cyanoacrylate (CA) fuming process?
A
CA (superglue) is heated inside a sealed chamber. Humidity as added, carrying the CA fumes throughout the chamber. The CA polymerizes (attaches itself) to the substances left by the friction ridges on the item.
2
Q
What is the purpose of dye staining items after being processed by way of Cyanoacrylate fuming?
A
It can help provide better contrast of the impression on a multicoloured background.
3
Q
To what temperature is CA heated to?
A
100 degrees Celsius (+/-5)
4
Q
At what temperature does CA turn into Hydrogen Cyanide Gas?
A
Approximately 200 degrees Celsius
5
Q
What is the name of the chemical/process that can differentiate between human and animal blood?
A
OBTI (Immunochromatographic Test)
- it is a presumptive test
- reacts with hemoglobin in the blood
- if positive for human blood, will show within 3-5 minutes
