Question

"White Powder

Appearance
Water
Iodine
Vinegar
What is it?
Unknown #1

Unknown #2

Unknown #3

Unknown #4

Unknown #5

Follow-up Questions:

1. In this activity, pure samples were tested. Would this be the case if you were investigating a crime in the real world? Explain your answer.
2. Were you able to identify the unknown samples in this lab? If so, how did you determine the identities? If not, what problems did you run into?
3. How do you think you could determine the contents in an unknown mixture of 2 of these white powders?
4. Use the information from class and the lab to explain how a forensic scientist could use screening and confirmation tests in order to determine the identity of an unknown substance. Cite examples from the lab."

Answer 1

The white powder could be a compound, an element, or a mixture, and additional tests would be needed to determine its identity. Forensic scientists use screening and confirmation tests to analyze unknown substances in crime investigations.

Step-by-step explanation:

The white powder can refer to various substances, so it is difficult to determine without additional information. It could be a compound, an element, or a mixture. Without more details, it is not possible to identify the unknown samples in the lab. To determine the contents of an unknown mixture of two white powders, you could use a combination of physical and chemical tests, such as solubility tests, melting point determination, and chemical reactions.

In the real world, when investigating a crime, pure samples may not be available. Forensic scientists often analyze complex mixtures of substances and use a combination of screening and confirmation tests to determine the identity of an unknown substance. Screening tests help narrow down the possibilities by producing specific reactions or characteristic properties. Confirmation tests, on the other hand, provide further evidence to confirm the identity of the substance.