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Re: Forensics C

Posted: February 17th, 2013, 5:33 pm
by JustDroobles
Skyrenify wrote:Can we have handwritten notes on the note sheet that we can bring?
Well I have not read this year's rules, so please go back to the 2013 rules and confirm for yourself, but you should be able to bring a 8.5"x11" sheet of paper with notes of any kind on both sides. Last year my partner and I printed our notes and then made some extra hand-written additions and diagrams as well. Also, I believe you should be able to write on your notes during competition, if that will help you somehow.

Re: Forensics C

Posted: February 17th, 2013, 5:37 pm
by Skyrenify
JustDroobles wrote:
Skyrenify wrote:Can we have handwritten notes on the note sheet that we can bring?
Well I have not read this year's rules, so please go back to the 2013 rules and confirm for yourself, but you should be able to bring a 8.5"x11" sheet of paper with notes of any kind on both sides. Last year my partner and I printed our notes and then made some extra hand-written additions and diagrams as well. Also, I believe you should be able to write on your notes during competition, if that will help you somehow.
Alright, much thanks. Good luck with your up coming competitions!

Re: Forensics C

Posted: February 21st, 2013, 2:52 pm
by allisonc524
computergeek3 wrote:
allisonc524 wrote:To perform flame tests on the unknown powders, is nichrome wire REQUIRED, or is there an alternative? The only thing I can find is platinum wire, and that's less common than nichrome... Any information you can provide would be greatly appreciated!
nichrome is not required...one of the best methods is to take wooden coffee stirrers and wet them. Dip the wet stirrer in the powder and light it on fire. The water prevents the wood from burning and gives a pretty nice burn.
How long do the stirrers need to be soaked for? Is it something that would need to be done before competition, then just bring in the wet stirrers?

Re: Forensics C

Posted: February 21st, 2013, 3:23 pm
by computergeek3
allisonc524 wrote:
computergeek3 wrote:
allisonc524 wrote:To perform flame tests on the unknown powders, is nichrome wire REQUIRED, or is there an alternative? The only thing I can find is platinum wire, and that's less common than nichrome... Any information you can provide would be greatly appreciated!
nichrome is not required...one of the best methods is to take wooden coffee stirrers and wet them. Dip the wet stirrer in the powder and light it on fire. The water prevents the wood from burning and gives a pretty nice burn.
How long do the stirrers need to be soaked for? Is it something that would need to be done before competition, then just bring in the wet stirrers?
Don't even soak them...just a few quick dips in a test tube of DI is sufficient. This allows the wood to not burn and the powders will stick to the stirrer...then, assuming you and your partner are good at IDing from flame tests, a few seconds in a flame will be perfect...if you need more time in the fire, it might help to just fill a test tube with DI at the beginning of the competition and let a few soak for a few minutes.

Re: Forensics C

Posted: February 21st, 2013, 5:24 pm
by allisonc524
computergeek3 wrote:
allisonc524 wrote:
computergeek3 wrote: nichrome is not required...one of the best methods is to take wooden coffee stirrers and wet them. Dip the wet stirrer in the powder and light it on fire. The water prevents the wood from burning and gives a pretty nice burn.
How long do the stirrers need to be soaked for? Is it something that would need to be done before competition, then just bring in the wet stirrers?
Don't even soak them...just a few quick dips in a test tube of DI is sufficient. This allows the wood to not burn and the powders will stick to the stirrer...then, assuming you and your partner are good at IDing from flame tests, a few seconds in a flame will be perfect...if you need more time in the fire, it might help to just fill a test tube with DI at the beginning of the competition and let a few soak for a few minutes.
Partner?? LOL, what partner? I'll have SOMEONE... but it'll be whomever had free time and was bored... Not much help. But thank you for the tip about coffee stirrers! I am very grateful!

Re: Forensics C

Posted: February 22nd, 2013, 9:38 am
by dholdgreve
pikachu4919 wrote:Is the formula for Benedicts Reagent CuSO4+NaOH or CuSO4+5H2O? sorry I've seen both and idk which one is correct or if neither is correct ...
I believe CuSO4+NaOH is actually Biuret's solution, an unstable reagent used to test for proteins

Re: Forensics C

Posted: February 23rd, 2013, 9:41 am
by googlyfrog
Does anyone have a solid way to distinguish between NaHCO3 and Na2CO3?

Re: Forensics C

Posted: February 23rd, 2013, 2:51 pm
by lmatkovic3
googlyfrog wrote:Does anyone have a solid way to distinguish between NaHCO3 and Na2CO3?
pH

Re: Forensics C

Posted: February 24th, 2013, 6:00 pm
by pikachu4919
lmatkovic3 wrote:
googlyfrog wrote:Does anyone have a solid way to distinguish between NaHCO3 and Na2CO3?
pH
Besides pH, Na2CO3 turns clear w/ lugol's solution although this reaction may take quite a bit of time to occur

Re: Forensics C

Posted: February 25th, 2013, 1:04 pm
by carliesmith123
I'm new at this event and I was wondering what I can do to prepare for it? Notes, tests etc.