Can't Judge a Powder B

[amerikestrel]

How specific does this get?

I mean, "this powder has a ph of 4" could be considered an inference if the observation would be "the paper turned a certain color".

Or, the fact that the powder has a ph of 4 could be considered an observation, if the inference would be "is it a base or an acid".

I think it could really go either way, unless it says something about this in the rules.

[AlphaTauri]

I would send in a clarification on that, because it seems it could go either way. I definitely wouldn't want to lose because I interpreted that section of the rules differently from the event sup. (Either way, appealing your score is a long, nasty process, but if you have the rule clarification, it makes it a lot easier.)

[HappySciencePie]

The rulebook has some sample questions that might help some of you to figure out what might be on the test. I guess this helps a little, unless you've read it already and are still confused.

a. Is the substance soluble in water?
b. If soluble in water, is the solution capable of conducting a current?
c. Does the substance react with an acid to produce a gas?
d. If soluble in water, what is the approximate pH of the solution?
e. If soluble in water, does the substance dissolve endothermically or exothermically?
f. Using a hand lens, what is the shape of the individual particles or are they too small to see?

So apparently, there will probably be some powders that are soluble in water. xD

[Sunshine]

I sent in a rules clarification, and got this for a reply:

"I would think that if you are given a key or color chart for the pH paper then the student should record both the color and the appropriate pH. I very often use wide range pH paper. If I asked this question at the National Tournament, I would score 5 points for color and pH and only 4 points for just one or the other."

[scienceawe]

Hi guys. I am a 6th grader and am doing Science Olympiad for the first time. I am wondering what some good tests for CJAP might be. I already know about all the standards (powder grain, luster, color, crystals or grains, qualities of crystals, general powder appearance, density, solubility, miscibility, hygroscopic or not, endothermic or exothermic reaction with water, ph or conductivity changes). I am also familiar with ionic or covalent compounds, but I am having difficulty in finding how to identify them with NaOH or HCI (I have been unable to find either's purpose, but know that I am looking for organic or inorganic testing and ionic or covalent testing, however I do know some other ways of identifying the latter by observing properties of the substance, such as solubility and conductivity.) I am also trying to find out about the use of Benidict's solution. Sorry for all the questions, but for chem tests, Google is almost useless. Thanks!

[robotman]

Hi guys. I am a 6th grader and am doing Science Olympiad for the first time. I am wondering what some good tests for CJAP might be. I already know about all the standards (powder grain, luster, color, crystals or grains, qualities of crystals, general powder appearance, density, solubility, miscibility, hygroscopic or not, endothermic or exothermic reaction with water, ph or conductivity changes). I am also familiar with ionic or covalent compounds, but I am having difficulty in finding how to identify them with NaOH or HCI (I have been unable to find either's purpose, but know that I am looking for organic or inorganic testing and ionic or covalent testing, however I do know some other ways of identifying the latter by observing properties of the substance, such as solubility and conductivity.) I am also trying to find out about the use of Benidict's solution. Sorry for all the questions, but for chem tests, Google is almost useless. Thanks!

well you dont have to identify the powder
all you really have to do is write down as many observations you can make about the powder and than take a test about it after

[EsaBellaBoosky]

My first tournament is tomorrow. Any first timer hints?

[robotman]

be detailed very detailed
just remember lab safety and that 20 minutes is a good amount of time so dont rush
also make sure you take everything you are allowed to take in as your kit

[scienceawe]

So you think that those are a good standard for tests to do? I already know what sticklers for precision the judges are, but the real difficulty will probably getting all those tests done in 20 minutes and recording the results. Do you know of any good places I can search for powder testing ideas, especially how to test with that sodium hydroxide (lye) and HCI (?).

Thanks!

[2win]

Here's a question: How are you supposed to find the mass of something without a balance?