Just Make sure you don't write the wrong formula than you would have problemsHappySciencePie wrote:Oh, I never knew that. Thanks for sharing. c:karatekid44 wrote:Also when taking the test, or when practicing, use the name of the test liquid that is given such as H20. Almost all of the judges will dock points for not using the scientific formula.
Most of the time it's easier to just write the formula anyway, so it's not like it's a hassle. :3
Can't Judge a Powder B
-
- Admin Emeritus
- Posts: 1447
- Joined: Sun Jun 29, 2008 7:37 pm
- Division: Grad
- State: TX
- Has thanked: 0
- Been thanked: 3 times
Re: Can't Judge a Powder B
-
- Member
- Posts: 31
- Joined: Sun Feb 21, 2010 11:27 am
- Division: B
- State: PA
- Has thanked: 0
- Been thanked: 0
Re: Can't Judge a Powder B
Hi, this is going to seem like kind of a stupid question, but I'm a little confused. When a powder is dissolved in water, and there is a color change or the clearness of the water changes (transparent to translucent or opaque) is the powder soluble in water? For some reason, I am having a lot of trouble with solubility and Google isn't helping me too much. Thanks !
-
- Admin Emeritus
- Posts: 1447
- Joined: Sun Jun 29, 2008 7:37 pm
- Division: Grad
- State: TX
- Has thanked: 0
- Been thanked: 3 times
Re: Can't Judge a Powder B
The easiest way is if the powder Totally disappears in water it is soluble (like you see the grains than maybe stir it a bit and than the grains are gone)
If you get a color change totally differant from the powder color (ie the powder is metalic looking and the water turns rustish colored (this most likely wont happen )) there is most likely a reaction that occurs not the powder dissolves with the exception of Cool Aid.
If it is cloudy the best thing to do is see if the powder settles out before saying that it is soluble or not if it doesnt settle out it is soluble if it does it isnt
If you get a color change totally differant from the powder color (ie the powder is metalic looking and the water turns rustish colored (this most likely wont happen )) there is most likely a reaction that occurs not the powder dissolves with the exception of Cool Aid.
If it is cloudy the best thing to do is see if the powder settles out before saying that it is soluble or not if it doesnt settle out it is soluble if it does it isnt
-
- Member
- Posts: 594
- Joined: Sat Jan 29, 2011 4:34 pm
- Division: Grad
- State: MI
- Has thanked: 0
- Been thanked: 0
Re: Can't Judge a Powder B
What are some good things to test for at the Regionals - an excessively nervous person 

100% of deaths are somehow caused by science.
Don't be a statistic.
Don't do science.
Naperville Central High School '17
Michigan State University Physics '21
GO GREEN GO WHITE
Don't be a statistic.
Don't do science.
Naperville Central High School '17

GO GREEN GO WHITE
-
- Admin Emeritus
- Posts: 1447
- Joined: Sun Jun 29, 2008 7:37 pm
- Division: Grad
- State: TX
- Has thanked: 0
- Been thanked: 3 times
Re: Can't Judge a Powder B
the Wiki Has a decent list to start with. Look through some of the old tests on the Test Exchange Wiki also
-
- Member
- Posts: 594
- Joined: Sat Jan 29, 2011 4:34 pm
- Division: Grad
- State: MI
- Has thanked: 0
- Been thanked: 0
Re: Can't Judge a Powder B
robotman09 wrote:the Wiki Has a decent list to start with. Look through some of the old tests on the Test Exchange Wiki also
OMFG like thank you tons!!!!!!!!!!!

Don't laugh, but in 3 of the 4 tryouts, I had disasters.
100% of deaths are somehow caused by science.
Don't be a statistic.
Don't do science.
Naperville Central High School '17
Michigan State University Physics '21
GO GREEN GO WHITE
Don't be a statistic.
Don't do science.
Naperville Central High School '17

GO GREEN GO WHITE
-
- Member
- Posts: 613
- Joined: Sat Dec 25, 2010 12:09 pm
- Division: C
- State: NJ
- Has thanked: 0
- Been thanked: 0
Re: Can't Judge a Powder B
Which sentence(s) would be an observation or inference?
"Once placed in the NaOH, the powder formed a gel."
"Once placed in the NaOH, the powder formed a gel-like substance."
"Once placed in the NaOH, the powder formed an alloid."
"Once placed in the NaOH, the powder formed a gel."
"Once placed in the NaOH, the powder formed a gel-like substance."
"Once placed in the NaOH, the powder formed an alloid."
-
- Admin Emeritus
- Posts: 1447
- Joined: Sun Jun 29, 2008 7:37 pm
- Division: Grad
- State: TX
- Has thanked: 0
- Been thanked: 3 times
-
- Member
- Posts: 1
- Joined: Thu Feb 24, 2011 1:07 pm
- Division: B
- State: TN
- Has thanked: 0
- Been thanked: 0
Re: Can't Judge a Powder B
Hello! I'm a mentor and I need a bit of help! Can we bring a graduated cylinder with us? We don't see that it is specifically mentioned, so we are afraid to bring it and get disqualified. However, we have noticed that some of the practice questions ask for the volume of the powder.
Would it be provided by the person running the event?
Thank you!
Would it be provided by the person running the event?
Thank you!