Chemistry, galvanic cell reaction equations, galvanic cell reaction equations

Al negative electrode, mg positive electrode.

Because Mg does not react with NaOH (or rather weakly) and Al reacts with NaOH, Mg does not react here and only acts as an electrode. Al acts as the negative electrode and is oxidized to Al3+, but then Al3+ combines with excess OH- to form ALO2-

Electrode Reaction Equation:

Negative electrode: 2al-6e-+8oh-=2alo2-+4h2o positive electrode: 6h2o+6e-=3h2+6oh-

Total reaction formula: 2al+2oh-+2h2o=2alo2-+3h2 electrode formula, you can write the total reaction formula first, and then split it up.

When writing the electrode formula, remember to consider whether the resulting substance reacts with the substance in solution. As in this case, the Al3+ generated by Al reacts with OH-.

Magnesium is the negative electrode and aluminum is the positive electrode

The positive pole shouts stool scale: 2h +2e = h (reduction reaction). Negative electrode: zn-2e = zn (oxidation reaction). Total reaction formula: zn+2h = zn+h.

Positive electrode: 2ag +2e = 2ag (reduction reaction). Negative electrode: Cu-2e = Cu (reduction reaction). Total reaction formula: Cu+2AG = Cu+2AG.

Principle: Electrode reactions are basically redox reactions, which should follow the conservation of mass, electron and charge. In addition to Zheng doing this, it is necessary to follow. The two electrode reactions are added together, and the total reaction formula of the battery is obtained after the electrons are removed.

Using this principle, the total reaction formula of the battery is subtracted from the known reaction formula of one electrode to obtain the anti-coarse response equation of the other electrode.

The negative electrode is the ferroelectrode: 2fe - 4e blind = 2fe the positive electrode i.e. the zinc electrode: o + 4e +2h o = 4oh The total electrode reaction equation:

2Fe+O +2H O = 2Fe 4OH Iron and zinc electrodes, immersed in sodium chloride solution (electrolyte) together, because iron is more active than zinc, it is easy to lose electrons, iron is oxidized into divalent iron into the solution, electrons flow from the iron sheet through the wire to the zinc mill aerial sheet, and the hydrogen ions in the solution obtain electrons from the zinc sheet and are reduced to hydroxide.

For inert electrodes:

Cathode: 2cu +4e = 2cu

Anode: 2H O + 4e = 4H + O

Total equation: 2cu +2h o=2cu+o +4h copper cong zinc galvanic battery, also known as Daniel battery, its positive electrode is copper electrode, immersed in copper sulfate solution; The negative electrode is a zinc plate, immersed in a zinc sulfate solution. The two electrolyte solutions are connected with a salt bridge, and the two poles are coarsely connected with wires to form a galvanic cell.

The dry batteries used in daily use are made according to the principle of galvanic batteries.

ok~~~

Negative electrode - iron, positive electrode - copper, electrolyte solution - dilute sulfuric acid"

Negative: Zn - 2E- = Zn2+

Positive: 2h+ +2e- = h2

Total cell reaction: Zn+2H+=Zn2++ H2

Step 1: First write out the chemical reaction that occurs in the galvanic battery, generally the negative electrode and the electrolyte solution react;

2. After changing to an ion equation;

3. Then mark the double-wire bridge, 4. According to the electrons gained and lost on the two-way bridge, write the electrode reaction of the positive and negative electrodes (negative electrode: electron loss, positive electrode: electron gain);

If you're a freshman in high school, then this "negative-iron, positive-graphite; Electrolyte solution - sodium chloride solution" is not required to be mastered, this "negative electrode - copper, positive electrode - silver, electrolyte solution - silver nitrate solution" you can try to write according to my steps.

Easy to learn the principle of galvanic batteries High School Chemistry Compulsory 2 It's really easy to learn chemistry.