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Can't Judge a Powder B
Posted: June 11th, 2009, 7:26 pm
by Jim_R
Discussion for Can't Judge a Powder B.
Re: Can't Judge a Powder B
Posted: August 3rd, 2009, 6:35 am
by 2win
so for this event, you have to be able to name powders? is that all?
Re: Can't Judge a Powder B
Posted: August 3rd, 2009, 7:25 am
by gneissisnice
Not even that, no time in the event do you have to ID the powder.
You have to write down observations, such as physical properties of the powder (color, relative grain size, solid), and it's reactions with other chemicals (does it effervesce in HCl? or react with NaOH?).
You have to write down everything you can think of, even if it's really obvious. Then you clean up and take a test, answering questions about the powder. You get 5 points for a correct answer with an observation, and 2 points for a correct answer without an observation. You have to number each observation, and then put the number down by the question that requires it.
That's basically the event. They generally give you boring, non-reactive powders too. And no observation is too trivial for them. At nationals one year, they gave us the powder in a bag which was numbered, they asked us what number was on the bag =/
Re: Can't Judge a Powder B
Posted: August 3rd, 2009, 10:09 am
by 2win
oh, okay. thanks!
Re: Can't Judge a Powder B
Posted: September 13th, 2009, 10:36 pm
by IZhou186
so is this a really easy and boring event that doesn't require much preparation?
Re: Can't Judge a Powder B
Posted: September 14th, 2009, 4:04 am
by robotman
no this is a fun event i have had the chance to do it at a Camp
and there is no science Olympiad event that is easy with the exception of pentathlon all the events you are in you need to study and work on if you wish to medal in them
Re: Can't Judge a Powder B
Posted: September 15th, 2009, 6:18 pm
by gneissisnice
IZhou186 wrote:so is this a really easy and boring event that doesn't require much preparation?
Though the premise is simple, competitions can get really hard sometimes.
You need to be able to communicate well, having one person write down the observations while the other does the tests.
At nationals one year, they gave us the basic reagents (HCl, NaOH, and water), and then they gave us phenolphthalein, bromothymyl blue, and some other chemical, and we had to due all the tests within 30 minutes.
My partner and I tried to work fast, but we were halfway through phenolphthalein when the time ended, with 2 more reagents to go. Of course, nearly every question on the test was about the reaction with phenolphthalein, bromothymyl blue, and the other one.
Needless to say, we got 51st =(.
It made me sad.
You're gonna want to practice and be able to execute the tests quickly and decisively.
Re: Can't Judge a Powder B
Posted: September 28th, 2009, 1:39 pm
by Science Guava
I was just researching this event and it seems like you should know more about how to make the right observations rather than trying to identify the powder usong these observations.

Although, I'm kind of nervous about what sorts of powders that are generally used. Has anyone who's done it before got some ideas? (pardon the grammar)

Re: Can't Judge a Powder B
Posted: September 28th, 2009, 2:03 pm
by robotman
you do not have to identify the powders there is a list of powders in the rules which are recomendations on what may be used
the only time i have doe it before was at SO camp and it really is just making as many accurate observations of the substance
i suggest learning the different ways to classify grains (size texture etc)
Re: Can't Judge a Powder B
Posted: October 5th, 2009, 5:24 am
by Amber259
isn't like food science