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Lemon juice as energy
Does lemon juice work in a clock as energy? If so, how? This is for a science fair project. I am in the 4th grade.
Evan B [last name deleted for privacy by Editor]- Slidell, Louisiana
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Not exactly, Evan. Let's compare to a battery: Flashlight batteries that you buy at a store have a zinc case, with a carbon rod in the center, and they are filled with a conductive black glop. The electricity in a battery is a result of the difference in the electrochemical potential between the zinc and the carbon, combined with the fact that the conductive black glop allows ions to travel from one electrode to the other. Your lemon battery has a zinc covered nail (galvanized nail) instead of a zinc case, a copper penny instead of a carbon rod, and lemon juice as the conductive solution instead of the black glop. The lemon juice is not the source of the electricity, the system is -- two different metals and a conductive solution connecting them.
++++++ Hello we are crying and we want to know why do we get less voltage from a lemon than from an apple..by using an analog multimeter, maybe we are doing something wrong can you help us, we are from 8th grade and we can't find an explanation why we get so little voltage from the lemon compared to other fruits, why did we get more from the apple, is the apple acidic? Rebecca B [last name deleted for privacy by Editor]student - Guatemala City, Guatemala |
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You are probably not using identical electrodes in the lemon, Cousin Rebecca. The voltage depends mostly on the two different metals that the electrodes are made of. It does not depend very much on the electrolyte (the apple juice or lemon juice). Try again using the same electrodes in the lemon as in the apple.
It may not be there forever, but here is a great YouTube video on lemon batteries --^
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 Ted Mooney, P.E. finishing.com Brick, New Jersey |
January 28, 2008
I found that all citrus fruits will power a small light bulb. Also if you cut two slits in to your fruit, stick a nail in one and a copper penny in the other slit, they will act as the plus and minus sides of a battery. The nail will be coated in zinc, and the penny will be made of copper. This will only work if the two metals are not touching. (Sometimes pennies aren't made with pure copper, so for best results, use a real copper wire). The nail and penny are scientifically entitled electrodes. The fruit juice is scientifically identified as an electrolyte. The flow from the minus to the plus side is the flow of electrons. The penny and nail are the conductors, which allow electrons to flow through them.
Electricity is produced by the flow of electrons. The electron flow is sometimes produced by chemical reactions. Some of these reactions including this are the zinc from the nail, the copper from the penny, and the citric acid from the fruit.
An average lemon should produce about 0.7 volts of electricity. An average orange will produce approximately
0.6 volts of electricity. A grapefruit will probably produce around 0.6 to 0.7 volts. A lime on average will produce about 0.5 volts of energy.If you want to measure the voltage, connect a volt meter to the wires to see how many of each fruit you will need to power the bulb's voltage. Keep adding fruit until you get the right amount of volts, then connect the light. Results may vary, due to the difference of acids in different fruit, and brand of fruit.
Allie and Kaylie
- Alden, New York
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November 22, 2008
HEY I'm MARIA I TESTED MANY MANY FRUITS. i have a question. What would be the hypothesis for this project? Maria G [last name deleted for privacy by Editor]- Florida December 8, 2008 Hi, Maria. Your hypothesis should be an educated guess about something, and it should be testable. Ideally it should involve independent variables you can alter and dependent variables that change in a cause & effect way when you alter the independent variables. So it would be nice if your experiment was more quantitative rather than qualitative. In other words, answering a yes/no question like "is 100 lemon batteries enough to run a computer" is quite impressive, but not quite as satisfactory a science experiment as saying "I believe that the voltage available from lemon batteries is cumulative, additive, and directly proportional to the number of batteries" and then graphing the number of batteries vs. the voltage you generate. If you accept this suggestion, just leave out "I believe that" and you have your testable hypothesis. Regards,
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November 26, 2009
I am doing a Science Fair project off of something I saw on TV. It was a lemon stereo I am using galvanized nails, copper, wire and radio , oh and a plug that looks kind of like what you would use to start up your car when the battery dies but it is a lot smaller and is not connected.I need help! Please respond ASAP! Please I'm in the 7th grade. Thanks for anything you can do.
KayLynn C [last name deleted for privacy by Editor]- Columbus, Georgia
November 2009
Hi, KayLynn. Unfortunately I did not see the TV show that you did, and I have no idea what you're talking about. Sorry! Hopefully another reader will remember it.
Regards,
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Ted Mooney, P.E. finishing.com Brick, New Jersey |