Forensics

[daydreamer0023]

Since no one's started it yet, I guess I will. What powder is used as a scotophor with designation P10 in dark-trace CRTs (such as in the Skiatron)?

[daydreamer0023]

I guess I'll try another question since the previous one didn't work out...

In fire arms, how does magnum differ from caliber?

[sciduck]

I guess I'll try another question since the previous one didn't work out...

In fire arms, how does magnum differ from caliber?

What was the answer to the first question? (Click to Show Hidden Text)

Caliber is the diameter of the internal barrel. Not actually sure what magnum is, but it's probably designating a gun that's bigger or more powerful than a certain caliber.

[daydreamer0023]

I guess I'll try another question since the previous one didn't work out...

In fire arms, how does magnum differ from caliber?

What was the answer to the first question? (Click to Show Hidden Text)

Caliber is the diameter of the internal barrel. Not actually sure what magnum is, but it's probably designating a gun that's bigger or more powerful than a certain caliber.

Magnum is basically a different measurement/style of cartridge. Anyhow, the answer to the first question was potassium chloride. Your turn!

[sciduck]

When ammonium chloride reacts with one of the reagents provided by the supervisor, it forms the tetraamine copper(II) ion. What color is this ion and what is the reagent?
Edit: By reagent, I mean iodine, HCl, NaOH, or Benedict's

[Magikarpmaster629]

So...this has been a problem for a long time since it's harder to write questions for it, but I don't think y'all are really going in the right direction with the Forensics QM right now. The questions you're asking just don't show up on tests- at nationals even, the questions asking for background knowledge are actually pretty easy. You're looking too far into it. What makes Forensics hard is knowing your process for identification really well, and being able to go through it really fast. As a former competitor I would recommend focusing on questions like "You observe a powder to dissolve in water, forms a precipitate when reacting w/ NaOH, and turn red in the flame. What is this powder?" (it would be Ca(NO3)2). That and some of the "study" questions that actually do come up (usually related to DNA, chromatography, fingerprints and lifting techniques, mass spec, chemical reactions, etc).

[sciduck]

So...this has been a problem for a long time since it's harder to write questions for it, but I don't think y'all are really going in the right direction with the Forensics QM right now. The questions you're asking just don't show up on tests- at nationals even, the questions asking for background knowledge are actually pretty easy. You're looking too far into it. What makes Forensics hard is knowing your process for identification really well, and being able to go through it really fast. As a former competitor I would recommend focusing on questions like "You observe a powder to dissolve in water, forms a precipitate when reacting w/ NaOH, and turn red in the flame. What is this powder?" (it would be Ca(NO3)2). That and some of the "study" questions that actually do come up (usually related to DNA, chromatography, fingerprints and lifting techniques, mass spec, chemical reactions, etc).

I agree, but the questions like the example you provided show up so often that I feel like people rarely get them wrong.
The question I posted about tetraamine copper(II) ion was actually I a question I got wrong on a previous test (because why would I bother remembering something that seems so obscure?)
Basically, I just don't know if this QM is supposed to represent the majority of the test questions or prep people for the obscure ones (because those are the ones that are usually missed).

[daydreamer0023]

So...this has been a problem for a long time since it's harder to write questions for it, but I don't think y'all are really going in the right direction with the Forensics QM right now. The questions you're asking just don't show up on tests- at nationals even, the questions asking for background knowledge are actually pretty easy. You're looking too far into it. What makes Forensics hard is knowing your process for identification really well, and being able to go through it really fast. As a former competitor I would recommend focusing on questions like "You observe a powder to dissolve in water, forms a precipitate when reacting w/ NaOH, and turn red in the flame. What is this powder?" (it would be Ca(NO3)2). That and some of the "study" questions that actually do come up (usually related to DNA, chromatography, fingerprints and lifting techniques, mass spec, chemical reactions, etc).

I agree, but the questions like the example you provided show up so often that I feel like people rarely get them wrong.
The question I posted about tetraamine copper(II) ion was actually I a question I got wrong on a previous test (because why would I bother remembering something that seems so obscure?)
Basically, I just don't know if this QM is supposed to represent the majority of the test questions or prep people for the obscure ones (because those are the ones that are usually missed).

I also agree. I'd also say that the obscurity of the questions depend on the test writer. The Nats test writer focuses more on identification vs. trivia knowledge.

To answer the question posed by sciduck, the ion is orange, the reagent is benedict's solution.

[sciduck]

So...this has been a problem for a long time since it's harder to write questions for it, but I don't think y'all are really going in the right direction with the Forensics QM right now. The questions you're asking just don't show up on tests- at nationals even, the questions asking for background knowledge are actually pretty easy. You're looking too far into it. What makes Forensics hard is knowing your process for identification really well, and being able to go through it really fast. As a former competitor I would recommend focusing on questions like "You observe a powder to dissolve in water, forms a precipitate when reacting w/ NaOH, and turn red in the flame. What is this powder?" (it would be Ca(NO3)2). That and some of the "study" questions that actually do come up (usually related to DNA, chromatography, fingerprints and lifting techniques, mass spec, chemical reactions, etc).

I agree, but the questions like the example you provided show up so often that I feel like people rarely get them wrong.
The question I posted about tetraamine copper(II) ion was actually I a question I got wrong on a previous test (because why would I bother remembering something that seems so obscure?)
Basically, I just don't know if this QM is supposed to represent the majority of the test questions or prep people for the obscure ones (because those are the ones that are usually missed).

I also agree. I'd also say that the obscurity of the questions depend on the test writer. The Nats test writer focuses more on identification vs. trivia knowledge.

To answer the question posed by sciduck, the ion is orange, the reagent is benedict's solution.

The reagent is right, but the color is dark/royal blue. The orange you are thinking of is copper(I) oxide, which is what give you the positive result w/ glucose.

I don't know how you want to proceed with the QM, but I'm fine with whatever. I've had my fair share of random trivia questions on tests, so both trivia and id questions are fine with me.

[daydreamer0023]

Oops. Oh well, I can't chemistry to save my life haha. How about this one:

Give an example of a surface that superglue fuming would be good fingerprint development method to use.