My science fair project is due in two days!
BUT I have a big problem: my science teacher disagrees with my project! I need help! I need to make sure that my project makes sense.
I'm measuring and comparing the electrolytes in different drinks (eg. milk, water, Gatorade, Red Bull...) in order to see which drinks' prices are "worth" the amount of electrolytes they contain.
This is what I did:
I tested the conductivity of each drink with a voltmeter and a battery three times. Then I took the price of each drink and divided it by its average voltage to get the price per volt.
Questions:
Will calculating the price per volt give me the price per electrolyte?
What is the relationship between electrolytes and voltages?
Any suggestions to improve my project?
Thank you!
URGENT: Need help on Electrolytes project!!
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science rules
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thetrans1ent
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Since the prices of different drinks are different depending on where you get them, you have an uncontrolled variable in your experiment (i.e., milk may cost $.50 at one store and $3.00 at another). To thwart this problem, you can stick to the manufacturers' suggested retail prices. By doing this, you would have to be very specific with what drinks you are testing for your report. However, even so, you have another problem: What determines if a certain price per voltage is "worthy"?
If you do away with price entirely, your question could be whether various drinks actually contain the amount of electrolytes advertised. For this case ideally you would want to test multiple bottles/cans of each drink--the larger the sample size, the better. Then you can run a statistical T-test.
Hope this helps.
If you do away with price entirely, your question could be whether various drinks actually contain the amount of electrolytes advertised. For this case ideally you would want to test multiple bottles/cans of each drink--the larger the sample size, the better. Then you can run a statistical T-test.
Hope this helps.
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ChrisG
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Hi Science Rules,
What is your teacher's concern with your project? Is the part that involves the prices of the different drinks?
To answer your first two questions, you need to understand the relationship between voltage, resistance, and electrolyte concentration. Here is a web page that describes many of the details:
http://www.tannerm.com/conductivity.htm
The main point that you should get from that page is that there are mathematical equations for the relationship between concentration and resistance (or conductivity) and that those equations are different for strong vs. weak electrolytes. Here is another page that has some information on strong vs. weak vs. non-electrolytes.
http://www2.aacc.cc.md.us/sciljtracey/C ... olytes.htm
I'd agree with thetrans1ent that using prices is problematic. I'd guess that electrolytes are very very cheap and that the main determinants of a soft-drinks price has more to do with marketing, distribution, packaging and other ingredients. Your question of which drinks have the most electrolyte per cost is a very interesting question, but it is more about consumer concerns than about science or engineering. You may want to adapt the project slightly so that it involves a more scientific hypothesis.
What is your teacher's concern with your project? Is the part that involves the prices of the different drinks?
To answer your first two questions, you need to understand the relationship between voltage, resistance, and electrolyte concentration. Here is a web page that describes many of the details:
http://www.tannerm.com/conductivity.htm
The main point that you should get from that page is that there are mathematical equations for the relationship between concentration and resistance (or conductivity) and that those equations are different for strong vs. weak electrolytes. Here is another page that has some information on strong vs. weak vs. non-electrolytes.
http://www2.aacc.cc.md.us/sciljtracey/C ... olytes.htm
I'd agree with thetrans1ent that using prices is problematic. I'd guess that electrolytes are very very cheap and that the main determinants of a soft-drinks price has more to do with marketing, distribution, packaging and other ingredients. Your question of which drinks have the most electrolyte per cost is a very interesting question, but it is more about consumer concerns than about science or engineering. You may want to adapt the project slightly so that it involves a more scientific hypothesis.