Electrolytes, electrical chemistry
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Electrolytes, electrical chemistry
I am testing electrolytes on a 9-v battery and so far the only thing I can use that works is salt water. Does anyone know of any other common household liquid that will light the light? thank you.
Other Electrolytes
You want to look for solutions like acids and bases and ionic crystals that form an electrolyte when dissolved. Things to try from around the house might be: vinegar, maybe meat tenderizer (not sure).
Check with your parents first about the items you want to try because some household chemicals can be dangerous if used inappropriately.
Ken -- Science Buddies Staff
Check with your parents first about the items you want to try because some household chemicals can be dangerous if used inappropriately.
Ken -- Science Buddies Staff
Follow up readings/questions - electrolytes
Here are the readings we got on the electrolytes test. A few conclusions
I can tell would be: the readings are lower with the salt because the
salt lights the light and takes more energy away from the 9 v battery.
The Tap water with salt, both warm and cold are higher than the distilled
water readings because the tap water already has other minerals in it.
but then why wouldn't the same be true without salt? Also, we thought that ions moved more freely in warm water, so why wouldn't the readings reflect this?
does any of this make sense to you Ken?
Thanks - a 7th grade mom
Cold Distilled Water 7.89 Cold Distilled Water with Salt 2.65
Warm Distilled Water 8.21 Warm Distilled WaterWith Salt 3.67
Cold Tap Water 8.38 Cold Tap Water With Salt 3.06
Warm Tap Water 8.16 Warm Tap Water With Salt 2.91
I can tell would be: the readings are lower with the salt because the
salt lights the light and takes more energy away from the 9 v battery.
The Tap water with salt, both warm and cold are higher than the distilled
water readings because the tap water already has other minerals in it.
but then why wouldn't the same be true without salt? Also, we thought that ions moved more freely in warm water, so why wouldn't the readings reflect this?
does any of this make sense to you Ken?
Thanks - a 7th grade mom
Cold Distilled Water 7.89 Cold Distilled Water with Salt 2.65
Warm Distilled Water 8.21 Warm Distilled WaterWith Salt 3.67
Cold Tap Water 8.38 Cold Tap Water With Salt 3.06
Warm Tap Water 8.16 Warm Tap Water With Salt 2.91
Your Readings
I'm not sure what the readings you gave represent. "Cold Distilled Water 7.89 Cold Distilled Water with Salt 2.65" What are you measuring when you say "7.89 and 2.65" and how are you measuring it?
Readings
The readings mean that when we put the voltage meter into the water, and tested with the various solutions, that is what happened to the voltage. i.e. it went down when we added salt because the light took up some of the electricity - that's what I am assuming?! But I don't understand the readings totally. Any ideas? Time is of the essence. I'm a single mom with no guy to help, and a child with ADHD that we are struggling with.
Thanks ken
Thanks ken
Measuring Resistance of the Electrolyte
Hope this isn't too late. I assume you have one lead from a battery going into the solution and the other lead connected to a light bulb and the second lead from the light bulb going into the solution.
What I'm still not sure is where you have the voltmeter in the circuit.
Normally in an experiment like this you would want to measure the current, in other words, the quantity of electrons that are flowing. One wire from the battery would go into the solution, the other would go to the ammeter (which measures current -- you probably have an ammeter setting on your "voltmeter") and then the other lead from the ammeter would go into the solution. The current would rise when you add salt. Using a light bulb instead of an ammeter is just another way to see when the current starts to flow.
This is a demonstration of Ohm's law (see http://jersey.uoregon.edu/vlab/Voltage/ or http://www.grc.nasa.gov/WWW/K-12/Sample ... mslaw.html). The resistance in your case is provided by the solution. Plain water has high resistance, salt water has low resistance (so current flows). The battery provides the voltage.
In fact, another way to do the experiment is to simply put the leads of a resistance meter into the solution and measure the resistance (I'm assuming you're using a battery powered meter -- this would be too dangerous if the meter is plugged into the wall.) Almost every "voltmeter" has a resistance meter function.
I hope this helps.
Ken -- Science Buddies Staff
What I'm still not sure is where you have the voltmeter in the circuit.
Normally in an experiment like this you would want to measure the current, in other words, the quantity of electrons that are flowing. One wire from the battery would go into the solution, the other would go to the ammeter (which measures current -- you probably have an ammeter setting on your "voltmeter") and then the other lead from the ammeter would go into the solution. The current would rise when you add salt. Using a light bulb instead of an ammeter is just another way to see when the current starts to flow.
This is a demonstration of Ohm's law (see http://jersey.uoregon.edu/vlab/Voltage/ or http://www.grc.nasa.gov/WWW/K-12/Sample ... mslaw.html). The resistance in your case is provided by the solution. Plain water has high resistance, salt water has low resistance (so current flows). The battery provides the voltage.
In fact, another way to do the experiment is to simply put the leads of a resistance meter into the solution and measure the resistance (I'm assuming you're using a battery powered meter -- this would be too dangerous if the meter is plugged into the wall.) Almost every "voltmeter" has a resistance meter function.
I hope this helps.
Ken -- Science Buddies Staff
A Picture
Here's a site that has a picture of what I described in the previous message. It's part way down the page: http://www.funsci.com/fun3_en/electro/electro.htm#1
Ken -- Science Buddies Staff
Ken -- Science Buddies Staff