The acidity and alkalinity of normal salt, is salt acidic or alkaline?

Na2SO4, NANO3, KNO3, and K2SO4 are all strong acids and alkali salts.

We can look at it this way, taking Na2SO4 as an example:

Na2SO4 is produced from 2NaOH + H2SO4 = + 2H2O.

Among them, H2SO4 is a strong acid, and NaOH is a strong base, so Na2SO4 is called a strong acid and strong alkali salt.

The same can be said for nano3 kno3 k2so4.

Regarding strong acids and strong alkaline salts, strong acids and weak alkaline salts I give you two examples:

Weak acid and strong alkali salt: Na2CO3, where H2CO3 is a weak acid and NaOH is a strong base.

Strong acid and weak alkali salt: NH4Cl, where NH4OH=NH3·H2O is a weak base, and HCl is a strong acid.

Chemicals that are not normal salts are equivalent to reverse reactions (hydrolysis) in aqueous solutions

An acid-base imbalance can occur.

Positive salts are in aqueous solution, and some can promote the ionization of water.

If it is formed by strong acids and bases, it will not promote the ionization of water.

If it is produced by strong acids and weak alkaline salts. Incomplete ionization of a weak base increases (relatively) H ions.

If it is a strong base and weak salt. The incomplete ionization of weak acids will increase the number of OH ions (also relative).

Therefore, our teachers have a rule: "The two strong are not obvious, and whoever is strong shows the sex." "Done?

Positive salts are not acidic or alkaline because they do not have a hydrolysis reaction.

If the acid base is a weak acid in the weak salt, it is alkaline.

If the metal ions are weak, it is acidic.

Because there is a hydrolysis reaction.

The cation in the salt comes from the base, so the hydroxide ion after the cation is the base; The anions in salt come from acids, so adding hydrogen ions is acid. So, when you look at what the nature of salt is, you have to do the above. After doing it, according to the knowledge of the strength of the acid and alkali, judge that the salt is strong acid and weak alkali, strong acid and strong alkali, strong alkali and weak acid.

For example, sodium sulfate can be regarded as a salt formed by strong alkali sodium hydroxide and strong acid sulfuric acid, so it is a strong acid and strong alkali salt.

Salt is neither acidic nor alkaline and is a neutral substance. Sea salt is mostly eaten in daily life, which is extracted and processed from seawater. Table salt can add more saltiness to the dishes people make and is an essential seasoning in life.

Table salt contains a necessary ingredient in people's bodies, and it is necessary to control the amount of salt when cooking every day, so as to supplement the nutrients in our body without affecting people's health.

Precautions

1. Sealed and stored.

Iodized salt. Under the influence of heat, light and wind, it is easy to oxidize and decompose and make iodine ineffective, so iodized salt should be stored in a covered colored sealed container. Store in a dry, cool place away from sunlight and air moisture. Eat as you go, don't buy too much at once and store it for a long time.

2. Avoid stir-frying at high temperatures.

Iodized salt will decompose into elemental iodine and volatilize when exposed to high temperatures, so do not use salt to "burst the pot" when stir-frying, and wait for the eight vegetables to mature before adding salt, which can reduce the loss of iodine.

Edible salt in the market has no expiration date.

but with iodine, zinc, selenium, calcium, riboflavin and other trace elements.

The shelf life of edible salt is one year.

Positive salt is a salt formed by the complete neutralization of acid and alkali, there will be no hydrogen ions in the acid, there will be no hydroxide ions in the base, only metal cations and acid ions. Salts in chemistry are divided into single salts and combined salts, single salts are divided into normal salts, acid salts, and basic salts, and combined salts are divided into compound salts and complex salts.

The positive salt is the product of complete neutralization of acid and base, but the aqueous solution of the normal salt is not necessarily neutral, such as the Na CO (sodium carbonate) solution is alkaline, and the (NH) so (ammonium sulfate) solution is acidic.

In the salt formed by the complete neutralization of acid and alkali, there will be no hydrogen ions in the acid, and there will be no hydroxide ions in the base, only metal cations and acid ions, and such salts are positive salts.

Classification of normal salts. 1. Strong acid and alkali salt.

Hydrolysis does not occur because the anions and cations ionized by their ionization cannot destroy the ionization balance of water, so they are neutral.

2. Strong acid and weak alkali salt.

We call the weak alkali part weak yang, the weak alkali ions can hold the hydroxide ions ionized from the water, destroy the ionization balance of the water, and make the ionization of the water move forward, as a result, the concentration of hydrogen ions in the solution is greater than the concentration of hydroxide ions, making the aqueous solution acidic.

3. Strong alkali and weak salt.

In the same way, the weak yin holds the hydrogen ions ionized from the water, so that the concentration of hydroxide ions in the solution is greater than the concentration of hydrogen ions, making the solution alkaline.

4. Weak acid and weak alkali salt.

The weak acid part holds the hydrogen, the weak alkali part holds the hydroxide root, generates two weak electrolytes, and then compares their ionization constants Ka, KB value (not the size of the degree of hydrolysis), at a temperature, the ionization constant of the weak electrolyte (also called the ionization equilibrium constant) is a fixed value, this comparison can be derived from what the salt is, who is strong and who is the nature, the ionization constant is a negative logarithm based on 10, who loses less who is bigger.

Hello, it is a pleasure to answer for you Is salt acidic or alkalineAnswer: Generally speaking, salt is neutral, neither acid nor alkaline, and has a pH of 7. But if it is a strong acid, a weak alkali salt or a weak alkali strong salt, it will show acidity and alkalinity.

For example, ammonium sulfate and ammonium chloride are weakly acidic, and the pH is generally 4-5. Sodium carbonate and potassium carbonate are alkaline, with a pH of 9-11.

How to distinguish the three salts:

1. Simple identification: there are H ions in acid salts, OH ions in basic salts, and none of oh ions in normal salts.

2. Complex identification: In the salt generated by the complete neutralization of acid and alkali, there will be no hydrogen ions in the acid, and there will be no hydroxide ions in the base, only the metal cation and the acid radical are separated, and such a salt is a positive salt.

Light cannot be correctly identified from the appearance, and it needs to be identified by chemical reactions or chemical properties.

Chemical properties of the three salts:

1. Acid salt: In addition to metal ions [or NH4+ (with metal ion properties)], there are hydrogen ions and anions (easily obtained electrons) are salts of acid ions.

2. Basic salts: In addition to acid ions, the anions generated during ionization also include hydroxide ions, and the cations are metal ions (or NH4+) salts.

3. Positive salt is a cation (volatile electron) generated during ionization, a salt with no hydroxide ions except for metal ions [or NH4+ (with metal ion properties)] and no hydrogen ions except for acid ions.

Chemical properties of acid-base salts.

1. Chemical properties of acids:

Acids + metal oxides.

Salt + water (acid + alkali salt + water).

Example: Fe2O3 + 6HCl = ==2FeCl3 + 3H2O2, acid + salt New acid + new salt.

For example: CaCO3 + 2HCl = = = CaCl2 + H2O + CO2 3, acid + highly active metal salt + hydrogen.

Example: Fe+2HCl===FeCl2+H2 4, acid can be used with acid-base indicator.

React. Example: Purple litmus solution turns red when exposed to acid.

The colorless phenolphthalein test solution does not change color when exposed to acid.

5. Acids can react with bases.

Acid + base === salt + water.

Example: HCl+NaOH===NaCl+H2O Supplement: HCl can be the same as AGNo3

Carbonate ion reaction.

H2SO4 can be the same...

2. Chemical properties of alkali:

1. Alkali + non-metallic oxide salt + water.

Example: Ca(OH)2 + CO2 ===CaCO3 + H2O2, alkali + salt neoalkali + new salt.

Example: Ca(OH)2+Na2CO3===2NaOH+CaCO3 3, alkali + acid water + salt.

For example: HCl+NaOH===NaCl+H2O4, base can react with acid-base indicator.

Example: Purple litmus solution turns blue when exposed to alkali.

The colorless phenolphthalein test solution turns red when exposed to alkali.

3. Chemical properties of salt:

1. Salt + metal with strong activity New salt + metal in the original salt.

Example: Fe+CuSO4===Cu+FeSO42, Salt + Salt Two new salts.

Example: naclagno3

nano3agcl↓

3. Acid + salt New acid + new salt.

Example: CaCO3+2HCl===CaCl2+H2O+CO2 4, alkali + salt neoalkali + new salt.

Example: Ca(OH)2+Na2CO3===2NaOH+CaCO3

The properties of acid-base salts are as follows:

Acid-base salts must contain non-metallic elements. Corrosive, the solution is acidic, can react with active metals, alkalis, certain salts and metal oxides react with active metals that are discharged before hydrogen to form salts and hydrogen, and react with indicators.

A pH-sensitive solution is not necessarily an acid, but an acid must be an acidic solution (i.e., acidic). Corrosive. The solution is alkaline and can react with acids, certain salts, non-metal oxides, some alkalis can react with certain metal oxides and react with indicators, the alkaline solution is not necessarily a base, but the alkali must be an alkaline solution.

What are acid-base salts:

Acid refers to compounds in which all cations produced during ionization are hydrogen ions; Base refers to a compound in which all the anions produced during ionization are hydroxide ions; Salts refer to compounds that form metal cations (or ammonium ions) and acid ions when ionized.

It can be abbreviated as: hydrogen head acid, hydroxide end alkali, metal start acid end is salt. Acids, alkalis, and salts are important knowledge points in chemistry learning.

How to learn chemistry well?

Study at consistent times of the day when your concentration is naturally high. Make your study habits part of your lifestyle and make the most of your fragmented time. Learn to make plans and set learning tasks into your daily schedule.

Qingxian attaches great importance to the consciousness and habit of output, and output is the killer weapon to transform knowledge into himself.

Make it a habit to prepare. Here is to correct the wrong view of most people: preview slows down the pace of learning, and preview is not necessary. On the contrary, preview can help you sort out your listening ideas, improve the efficiency of listening, reduce the review time after class, and take the initiative to win half the victory.

Psychological construction is equally important, even if you feel slack in your heart, you should encourage yourself to answer the wheel sedan chair, adjust Kiriten in time, and remember that people can have negative emotions such as "I want to learn, I am really boring to learn, and learning is very hard". Focus on memorizing hard-to-remember knowledge points, quickly memorize them when encountered, and review and memorize them in the next few days.

Make it a habit to do the little things quickly. This is also a very important habit. The top ones do their own things, and the backward ones don't blindly compare. If you can't reach the big goal, hurry up and set a small goal.

If you can't do the difficult problems, pick the easy ones that suit you to do them. The most terrible thing in life is that you can't do big things, you can't do small things, you can't do high, you can't do low, you can't go up, you can't go down. So let ourselves never give up.

Learn to make mind maps, note down the key points while listening during class, and then review the content of the class to make a mind map. Pay attention to the interaction of thoughts, rather than simply sitting there with a dead brain and thinking stupidly.