How to judge the positive and negative electrodes of a dry battery, how to judge the positive and ne

1. The first type: the positive and negative electrodes of the galvanic battery are determined by the electrode material, the relatively active metal is the negative electrode, and the negative electrode undergoes oxidation reaction; The less reactive metal (or non-metal and some oxide) is the positive electrode, and the positive electrode undergoes a reduction reaction.

As long as it is judged that the electrode is a reduction reaction, it is a positive electrode, and vice versa.

2. The second type: the dry battery has a protruding cap from the shape of the positive electrode, and the top of the battery also has (+) written on the positive electrode.

Experimental judgment method: use the digital multimeter of the measuring instrument, adjust to the DC voltage measurement file, the positive and negative meter rods are connected correctly, the value is positive, and the opposite display is negative, if it is a pointer multimeter, connect the opposite polarity of the pointer and reverse bias.

From the shape of the dry battery, the end of the protruding cap is the positive electrode, and the top of the battery also has (+) written on the positive electrode.

Experimentally judged words:

Use the measuring instrument digital multimeter, adjust to the DC voltage measurement file, the positive and negative meter rods are connected correctly, the value is positive, and the opposite display is negative, if it is a pointer multimeter, connect the opposite polarity of the pointer and reverse bias.

Generally, the plastic film wrapped around the battery will have a symbol of [+], + is the positive pole, and - is the negative pole.

If my answer satisfies you, thank you!

University Galvanic Cell Symbol Writing Rules:

The plus and minus signs are written on both sides, i.e. "(- written on the far left," (written on the far right.) The symbol " " indicates the boundary between different phases, and the " " indicates the salt bridge.

Note: The two phases with the split interface are separated by a single vertical bar; The two phases that are mixed together without a partition interface are separated by a comma. Some phases need to be followed by parentheses, and the concentration, pressure, etc. should be indicated in parentheses.

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Identification of positive and negative electrodes of battery:

Method 1: In the case of the blurred "+" sign, the battery pole painted in red represents the positive pole, while the pole painted with the blue mark is the negative pole. If the battery has been used for a long time, it may be dull in color.

But generally speaking, the slightly thicker pole is the positive electrode of the battery, and the slightly thinner pole is the negative electrode of the battery.

Method 2: Use the DC voltmeter to determine the positive and negative poles of the battery. Connect the battery to the DC voltmeter. In the case that the voltmeter needle indication is normal, the positive pole of the battery is connected to the positive pole of the voltmeter, and the negative pole of the voltmeter is the negative pole of the battery.

In addition to using a multimeter to measure, look at the +-marker, look at the color mark of the electrode, etcYou can also use potato discrimination, where two electrodes are connected and inserted into the cut potato section, and the potatoes around the wire turn green to the positive electrode.

How to judge the positive and negative electrodes:

1. The negative electrode undergoes oxidation reaction and loses electrons; The positive electrode undergoes a reduction reaction and electrons are obtained.

2. The one pole in which oxygen participates is positive--abbreviation: oxygen is positive;

3. Lively metal is generally a negative electrode - brief note: lively negative (live off a shrew);

4. The positive electrode of the one pole of cation shift - abbreviation: positive direction;

5. The pole with increased valence is negative - brief note: high and negative price (married to a rich and handsome);

6. Positive and negative negative: the positively charged one moves to the positive electrode; The negatively charged moves towards the negative electrode.

7. Electrons do not go into the water, and ions do not go ashore: electrons come out of the negative electrode and go to the wire, not the solution; Ions only move freely in the solution and do not travel wires.

There are six ways to do this.

Method 1: Judge according to the material of the two poles. Generally, active metals are negative electrodes, and less active metals or non-metals that can conduct electricity are positive electrodes;

Method 2: Judge according to the electrode phenomenon. Under normal circumstances, the kung fu electrode gradually dissolves into the negative electrode, and the positive electrode that can release gas when the electrode is weighted;

Method 3: Judge according to the electron-hydraulic direction. The electron outflow is the negative electrode, the electron inflow is the positive electrode, or the positive electrode of current outflow and the negative electrode of current inflow;

Method 4: Determine the directional movement direction of the ions in the electrolyte solution in the galvanic cell. The negative electrode is the anion flow direction, and the cation flow direction is the positive electrode;

Method 5: Judge according to the changes that occur at the poles of the galvanic battery. The negative electrode is the negative electrode that causes oxidation when the electrons are lost, and the positive electrode is the positive electrode that is reduced when the electrons are obtained.

Method 6: Judge the electrode according to the electrolyte solution. The electrode that can react with the electrolyte solution is the negative electrode, and the electrode that cannot react with the electrolyte solution is the positive electrode.

For example, magnesium and aluminum are electrodes, and sodium hydroxide solution is electrolyte solution, although magnesium is more active than aluminum, but because magnesium does not react with sodium hydroxide solution, aluminum can react with sodium hydroxide solution, so aluminum is the negative electrode and magnesium is the positive electrode.

The positive and negative poles of the power supply are due to the potential difference.

Or the presence of voltage. A high electric potential is called the positive electrode, and the current flows from a high electric potential to a low electric potential, that is, from the positive electrode. The electric potential is due to the electric field. Along the direction of the electric field, the electric potential decreases, and against the direction of the electric field, the electric potential increases.

Generally speaking, next to the positive terminal post will be a + symbol, and the negative terminal post will be a - symbol. When the polarity mark of the battery is blurry and the positive and negative poles can not be seen clearly, you can check the color of the pole to judge, generally the red pole represents the positive pole, and the blue pole represents.

The positive and negative poles of the battery can be viewed as follows: 1. The positive and negative poles can be judged according to the identification symbols on the battery, generally there will be a + symbol next to the positive terminal post, and the negative terminal post is a - symbol. 2. When the polarity mark of the battery is blurry and the positive and negative poles can be viewed, you can check the color of the pole itself, generally the red pole represents the positive pole, and the blue pole represents the negative pole.

The red pole is the positive electrode, and the black pole is the negative electrode.

You can also look at the nameplate marking, facing the nameplate marking on the battery housing, and the pole at the top right of the nameplate mark is the positive pole.

Check the thickness of the pole, the thick end of the pole is the positive pole of the battery, and the thin end of the pole is the negative pole of the battery.

It can be measured, and the two terminals of the positive and negative poles of the DC voltmeter are respectively connected to the two poles of the battery, and the pointer is turned to the positive pole, then the pole connected to the positive pole is the positive pole of the battery, and the pole connected to the negative pole is the negative pole.

You can also look at the chemical reaction, the two wires connected to the battery pole are soaked in dilute sulfuric acid solution, at this time, there are bubbles around the wire head, and the negative pole that produces more bubbles is the positive electrode. 6. It can also be compared and tested with a high-rate discharge meter and a battery with obvious polarity marks, and judged according to the deflection direction of the gauge hand.

If the positive and negative electrodes are not indicated, they cannot be seen, but if they are batteries, they can certainly be seen because there are production standards.

To see whether the positive or negative electrode of an electrode is generally speaking, if it is a No. 5 battery or a No. 7 battery, then it depends on its direction, for example, the end with a metal tip is the positive electrode.

It depends on what kind of battery it is. There are positive and negative signs, marked with red paint, and there are also other ways to mark.

If there is a plus sign on the battery, then this represents the positive pole. If the minus sign is displayed on the battery, then it represents the negative pole. If the plus and minus signs on the battery are blurred, the positive pole is usually painted red, and the battery pole painted blue is the negative pole.

In addition, you can use the voltmeter to check the electricity.

Hello friends, the positive and negative poles of the battery are generally displayed, and they are marked on them. The plus sign is the positive pole and the symbol is the negative pole. Hope it helps.

The positive and negative poles of the battery are easy to judge, and the end of the + sign is the positive pole, and the other end is the negative pole.

Looking at the positive and negative poles of the battery, generally marked with a plus sign on the top of the battery, it is the positive pole of the battery, and the one marked with a minus sign is the negative pole of the battery.

The metal of the battery housing is generally the negative electrode, and the separate pole is the positive electrode.

The positive and negative poles of the battery are marked with positive and negative marks at both ends of the battery, and they are judged according to the marks.

I think if you want to distinguish the positive and negative poles of the battery, it is very simple, under normal circumstances, their positive and negative poles are correspondingly marked, the positive pole is a plus sign, and the negative pole is a minus sign.

Generally, the top of the battery is marked with a positive or negative electrode, the positive electrode represents a plus sign, and the negative electrode is a minus sign.