Sodium reacts with salt solution Why react with water in the first place

The reason why sodium reacts with salt solution and first reacts with water:

1.The reason for the reaction with acid is that sodium actually reacts with hydrogen ions, and the hydrogen ions ionized by acid are much larger than the hydrogen ions from water electrons, so if the hydrogen ions ionized by acid and the hydrogen ions ionized by water compete for sodium, the hydrogen ions ionized by acid must win. If it reacts with salt, the metal ions ionized from the salt are hydrated ions, that is, the metal ions are replaced by water molecules.

Sodium must first come into contact with water before it can come into contact with metal ions.

2.This is because the bicarbonate ion contains one hydrogen, which has a small atomic radius and strong polarization, making sodium bicarbonate.

subject to great polarization will be used than sodium carbonate.

It tends to be a covalent compound, so it is less soluble in water than sodium carbonate.

Na is put into CuSO4 solution, before the water reaction, in essence, it is a reaction with hydrogen ions, this reaction process is more complicated, because the activity of Na is too strong, the outer electrons are very easy to lose, because in the aqueous solution, no matter how high the concentration of CuSO4 is, it is far lower than the amount of water, and Na is put into the solution, because its density is lower than that of water, so Na floats on water, reacts before water, does not contact with Cu ions, reacts to generate NaOH, resulting in an increase in the concentration of OH ions, It combines with Cu ions to form a blue flocculent precipitate, which reduces the concentration of OH and Cu in the solution, and the reaction between Na and water intensifies, and the reaction moves in the positive direction step by step until the reaction is terminated (this involves chemical equilibrium, ionization equilibrium, etc.) (the chemical equation is not written, if you write the equation, it is easy to understand).

The acid solution ionizes more H+ in water and reacts more easily with Na element.

Sodium is put into a hydrochloric acid solution and reacts with hydrochloric acid first, and then with water, because the essence is that sodium reacts with hydrogen ions, and then a subsequent reaction occurs. Because the concentration of hydrogen ions in hydrochloric acid is higher than that in water, it reacts with hydrochloric acid first.

Chemical reaction sequence:

1. The order of reactions between compounds:

When acid, alkali and salt are mixed, reactions can occur between acid and salt or between alkali and salt, and attention should be paid to:

1) If there is a redox reaction, consider the redox reaction first, and then consider the metathesis reaction;

2) Metathesis reaction, first consider the acid-base neutralization reaction, and then consider the reaction between acid and salt or between alkali and salt;

3) If multiple similar reactions can occur, the weaker the electrolysis of the product or the smaller the solubility of the precipitate, the reaction will be carried out first;

Second, the order of order caused by the actual operation of the experiment:

When adding a solution or introducing gas into a suspension, the reaction with the solution is considered first, and then the reaction with the solid in the system;

3. The sequence of redox reactions:

The essence of redox reaction is the reaction of electron transfer between reactants, so the stronger the ability of the oxidant to gain electrons, the stronger the ability of the reducing agent to lose electrons, and it is easier for electron transfer to occur between the two strengths;

Fourth, the sequence of discharge on the electrodes in the electrolytic cell.

The cathode of the electrolytic cell undergoes a reduction reaction, the anode undergoes an oxidation reaction, and the cations in the solution adsorbed on the cathode obtain electrons, so the strength of the oxidation of several cations in the solution should be considered, and the reducibility of the electrode itself should also be considered; If the electrolysis is an aqueous solution of a substance, it generally does not involve ion discharge after H+ and OH-.

5. Common reaction sequence problems in alkali metal compounds:

There are two important reactions that are often involved with Na2O2:

2na2o2

2h2o4naoh

o2；2na2o2

2co22na2co3

O2 uses these two reactions for chemical calculations, especially those involving mixtures of Na2O2 and CO2 and H2O.

First, Na2O2 reacts with CO2, and if Na2O2 is left, then consider the reaction with H2O.

Sodium is put into dilute hydrochloric acid and reacts with hydrochloric acid first, and the excess sodium reacts with water, and the essence of the reaction between sodium and the above substances is the replacement reaction between sodium and H.

1101 Reaction of sodium carbonate, sodium bicarbonate and hydrochloric acid.

The chemical equation for the reaction of Na and H2O is: 2Na + 2H2O = 2NaOH + H2.

Analysis: The reaction between sodium and water is to ignite and explode, luminous and warm, and the sodium-water reaction refers to the fact that sodium and water potatoes will slowly heat up when they are in contact with or steam, resulting in the phenomenon of explosion and luminescence, which is a strong chemical reaction.

Phenomena of Na and H2O reactions:1. After the metal sodium is placed in water, the sodium floats on the water surface.

2. Sodium swims rapidly on the surface of the water and has a slight hissing sound.

3. The sodium melts into a shiny ball.

4. After the reaction, phenolphthalein is dropped into the solution, and the solution turns red.

5. The generated gas can be ignited by hand, and there is a banging sound.

The above content reference: Encyclopedia - sodium.

Summary. Hello, dear dear, the reason for reacting with acid first is that sodium actually reacts with hydrogen ions, and the hydrogen ions ionized by acid are much larger than the hydrogen ions from water electrons, so if the hydrogen ions ionized by acid and the hydrogen ions ionized by water compete for sodium, it must be the hydrogen ions ionized by acid to win. If it reacts with salt, since the metal ions ionized in the salt are hydrated ions, sodium must first come into contact with water before it can come into contact with metal ions.

Hello dear and acid reaction first failed because sodium is actually reacted with hydrogen ions, and the hydrogen ions ionized by acid are much larger than the hydrogen ions from water electrons, so if the hydrogen ions ionized by acid and the hydrogen ions ionized by water compete for sodium, it must be the hydrogen ions ionized by the acid residue shed to win. If it reacts with salt, since the metal ions ionized in the salt are hydrated ions, sodium must first come into contact with water before it can come into contact with metal ions.

Sodium is very metallic, unlike ordinary D-block transition metals such as iron and copper, and reacts with water much faster than ions in solution.

Sodium reacts with salt solution, first with water, because the metal ions ionized in the salt are hydrated ions, that is, the metal ions are surrounded by water molecules, sodium must first contact with water before it can contact with metal ions. Therefore, sodium first reacts with hydrogen ions ionized by water to produce sodium hydroxide.

At this time, if the sodium hydroxide can no longer react with the ions in the solution, such as the salt solution is sodium chloride solution, the reaction will stop at this time; However, if there are substances in the solution that can react with sodium hydroxide, such as the salt soluble liquid is a copper sulfate solution, it will react with copper ions, so it should be analyzed together with the subsequent reaction.