If you want to get higher voltage, you can connect multiple fruit batteries in series. Do you have to be the same fruit? Can you connect different fruit batteries in series? What's more, we need to write the experiment report about fruit battery. How should we write it? We haven't learned those formulas yet.

If you want to get higher voltage, you can connect multiple fruit batteries in series. Do you have to be the same fruit? Can you connect different fruit batteries in series? What's more, we need to write the experiment report about fruit battery. How should we write it? We haven't learned those formulas yet.

Different fruit batteries can be connected in series
1、 The purpose of the experiment is to make a fruit battery with various fruits, and to compare the relationship between the pH value of fruits and the voltage produced
2、 Experimental requirements: master the use of voltmeter
3、 Experimental principle: the battery needs to use two kinds of metals to make it a positive and negative electrode. Between them, there are conductive substances such as hydrochloric acid or lye. These substances are generally solubilized and called electrolytes. Electrolytes can free metal ions. Generally speaking, any metal touching the electrolyte will release electrons and become positively charged ions
The reaction formula of fruit battery is as follows:
Anode (positive): Zn (s) → Zn2 + (AQ) + 2E - or Ni (s) → Ni2 + (AQ) + 2e-
Cathode: 2h + (AQ) + 2E - → H2 (g)
4、 Experimental equipment: measuring equipment: voltmeter, ammeter, wire, clamp, pH test paper
Battery pack: orange, lemon, apple
Plate: copper, zinc
5、 The experimental steps are as follows: (1) take two different fruits with similar weight (the error is less than 2G), cut them in half, measure the pH value of each fruit, and take the average value of the same fruit to get the pH value of each fruit;
(2) As shown in the figure below, zinc and copper pieces are inserted at both ends of the fruits to connect the four pieces of fruits in series with the light-emitting diode;
(3) The voltage and the current through the LED of these fruits were measured
7、 Conclusion: the lower the pH value, the higher the voltage

Positive and negative electrodes of fruit battery
The positive and negative electrodes of fruit battery were measured by three methods

1. Use diode (specific method you should know it) 2. Copper out of the positive, zinc out of the negative 3. Use an ammeter to see the direction of the pointer deflection, how to do it. Contact the textbook to think about it. 4. Use the magnetic effect of the current, put a compass on the side to see the direction of the N pole and S pole (and connect

How to judge the positive and negative poles of fruit battery

There are two ways to judge the positive and negative poles of fruit battery
(1) Judging from the activity of metal: the electrode of fruit battery generally adopts two kinds of metal with different activity. The active metal is easy to lose electrons and is the negative electrode; the less active metal is the positive electrode
(2) Try to touch with ammeter: because the voltage of fruit battery is directly related to the type of fruit, generally, the voltage of fruit battery is low, about 0.5V. For such a low voltage, we can use the touch test method of ammeter: connect the "+" terminal of ammeter to one pole of fruit battery, and the "-" terminal to a wire, Try to touch another electrode with the other end of the wire. If the ammeter turns forward, it means that the "+" terminal is connected to the positive electrode; if the ammeter deflects, it means that the "+" terminal is connected to the negative electrode
Note: try to touch the method must be mastered, that is, requirements: immediately connected, immediately separated

How to judge the positive and negative pole of fruit battery?
Is there a fixed answer? For example, if a fruit battery has a copper sheet and an iron sheet, the iron sheet is negative
Because I did a similar problem, I just said copper and iron, and then I was embarrassed
How to judge with chemical knowledge?
Oh, my God, the original question is only to judge the positive and negative, not to use the instrument

It's OK to use a voltmeter. It doesn't need to be sensitive. The voltmeter can directly measure the voltage at both ends of the battery. You connect one of them to a positive one and the other to a negative one, and then look at the pointer of the V meter. If the normal deflection means that the connection is correct, then the positive one is positive. If the left deflection is wrong, then the positive one is negative