How to tell if a substance is a strong or weak electrolyte

Strong electrolytes vs. weak electrolytes.

The formula for judging electrolytes is as follows, 1. Salts, strong alkalis, and strong acids are strong electrolytes. 2. Weak acids and bases are weak electrolytes. 3. Compounds with weakly polar covalent bonds are weak electrolytes. 4. Compounds with ionic bonds and strong polar bonds are strong electrolytes.

Determine the electrolyte formula.

In summary, strong and weak electrolytes can be judged from three aspects: ionization degree, chemical bond, and compound genus, and in addition, the three elements that distinguish strong and weak electrolytes are melting, electrical conductivity, and compounds.

Electrolytes generally refer to compounds that are dissolved in aqueous solution or can conduct electricity in the molten state, and are divided into two categories: strong electrolytes and weak electrolytes according to the degree of ionization, and almost all of them are ionized strong electrolytes.

Strong electrolytes include active metal oxides, sulfuric acid, calcium carbonate, copper sulfate and other substances, weak electrolytes include a small amount of salt, acetic acid, ammonia monohydrate, lead acetate, mercuric chloride and other substances, in addition, water is extremely weak electrolyze.

Compounds that can conduct electricity when dissolved in water or in the molten state are electrolytes. This definition can be broken down into three elements: melting or dissolving.

It can conduct electricity. Compound. However, when judging the strength of electrolytes, it is not clear which covalent compounds with polar bonds are strong electrolytes and which are weak electrolytes.

What are the bases for judging strong and weak electrolytes?

1.Generally speaking, strong and weak electrolytes can be judged from the following three aspects: Degree of ionization.

Chemical bonds. Compound genus. When there is a contradiction between these three aspects, the main distinguishing criterion is the degree of ionization, that is, the electrolyte that is completely ionized is a strong electrolyte.

Partially ionized electrolytes are weak electrolytes.

2.Distinguish strong and weak electrolytes from chemical bonds and genus of compounds.

1) Compounds with ionic bonds and strong polar bonds are strong electrolytes. (2) Salts, strong alkalis, and strong acids are strong electrolytes. 3. Compounds with weakly polar covalent bonds are weak electrolytes. (4) Weak acids and weak bases are weak electrolytes.

3.It should be noted that: (1) BaSO4 in aqueous solution is almost non-conductive due to its very small solubility, while a small fraction of dissolved BaSO4 is completely ionized and conducts electricity when melted.

Therefore, BaSO4 is a strong electrolyte that is insoluble. (2) When CO2, SO2 and NH3 are dissolved in water, the generated H2CO3, H2SO3 and NH3·H2O can conduct electricity, and CO2, SO2 and NH3 cannot be said to be electrolytes, but can only be said to be H2CO3, H2SO3 and NH3·H2O are electrolytes and are weak electrolytes. (3) HF (hydrofluoric acid) contains strong polar bonds, and its aqueous solution has a small degree of ionization due to factors such as hydrogen bonds, so hydrogen fluoride is a weak electrolyte.

4) The strength of electrical conductivity is not directly related to the judgment of strong or weak electrolytes. Because a strong electrolyte with a very thin concentration can also be very weakly conductive, and a weak electrolyte with a certain concentration can also be more conductive. Even for weak electrolytes, the conductivity changes as the concentration decreases.

4.In summary, strong and weak electrolytes cannot be classified according to the intrinsic properties of substances, and the main basis for judgment is whether they can be completely ionized in aqueous solution.

The difference between a strong electrolyte and a weak electrolyte is the degree of ionization (i.e., solubility) of the aqueous solution.

Non-electrolytes: 1. Non-metallic oxides: carbon dioxide, sulfur dioxide, carbon monoxide, sulfur trioxide, nitrogen dioxide, nitric oxide.

2. Most organic matter: methane, ethanol, sucrose (except organic acids and organic salts).

3. Non-metallic compounds: ammonia.

Weak electrolytes, weak acids, weak bases, water, such as:

1. Weak acids: carbonate H2CO3, sulfurous acid H2SO3, acetic acid CH3COOH, hydrosulfuric acid H2S hydrofluoric acid, HF silicic acid, H2SiO3, orthosilicic acid H3SiO4, all organic acids.

2. Weak alkali: ammonia monohydrate all hydroxide metal R (OH) except for strong alkali.

3. Water H2O is also a weak electrolyte.

Strong electrolytes, strong acids, strong bases, and most salts [including soluble and insoluble] such as:

1. Strong acid: HCl H2SO4 sulfuric acid Hno3 nitric acid HBR hydrobromic acid HI hydroiodic acid HCO4 perchloric acid.

2. Strong alkali: Naoh Koh Ba (OH) 2 barium hydroxide CA (OH) 2 calcium hydroxide.

3. The vast majority of salts: all the salts seen in high school are strong electrolytes, metal compounds: a, oxides:

Calcium Oxide, CA, Sodium Oxide, Na2O, Magnesium Oxide, Mgo, Al2O3 Oxide, Zinc Oxide, Zno Oxide, Iron Oxide, FeO, Fe2O3, Copper Oxide, Cuo, Mercury Oxide, Hgo, Silver Oxide, Ag2O.

B. Peroxide compound: sodium peroxide Na2O2.

C. Metal carbide: calcium carbide CaC2.

D. Metal sulfides: calcium sulfide Cas2 ferrous sulfide FeS2.

Judgment method: 1. Electrolyte is a compound that can be ionized under certain conditions, while non-electrolyte cannot be ionized.

2. Common substance categories: electrolytes are generally acids, alkalis, salts, typical metal oxides and some non-metal hydrides. Non-electrolytes are typically non-metallic oxides, some non-metallic hydrogen-positives, and the vast majority of organic compounds.

Some covalent compounds can also conduct electricity in aqueous solutions, but there are also solid electrolytes that are conductive** related to the migration of ions in the crystal lattice.

According to the degree of ionization, it can be divided into strong electrolyte and weak electrolyte, almost all of which are ionized by strong electrolytes, and only a small part of which are ionized by weak electrolytes.

Pure water is almost non-conductive, indicating that water is a weak electrolyte. Water molecules are ionized to form hydrogen ions and hydroxide ions. The pH of water = 7, indicating that the equilibrium constant of this ionization reaction is 10 to the minus seventh power.

In other words, only one of the 10 water molecules to the seventh power has an ionization reaction, resulting in hydrogen ions and hydroxide ions.

Electrolytes that are almost completely ionized in aqueous solution are called strong electrolytes; Otherwise, it is a weak electrolyte.

Strong electrolytes generally include: strong acids and bases, and most positive salts.

Weak electrolytes: weak acids, weak bases, such as; Acetic acid, ammonia monohydrate (NH3·H2O), and a few salts such as lead acetate and mercuric chloride. In addition, water is a very weak electrolyte.

First of all, it is necessary to understand that electrolytes are chemical compounds that can conduct electricity (electrolyze into cations and anions) and produce chemical changes when dissolved in an aqueous solution or in a molten state.

According to that definition, a compound that can be fully ionized is a strong electrolyte, which can be energized, and the strength of the conductive ability can be judged!

Depending on the degree of ionization, the strong electrolyte is fully ionized after being dissolved in water, while the weak electrolyte is only partially ionized!

Strong acids, strong bases, salts: are strong electrolytes.

Strong electrolytes: electrolytes that are almost completely ionized in water or in the molten state Weak electrolytes: electrolytes that are only partially ionized in water or in the molten state The strength of the electrolyte is related to the chemical bond, but not by the type of chemical bond.

Strong electrolytes contain ionic bonds or strong polar bonds, but those containing strong polar bonds are not necessarily strong electrolytes, such as H2O, HF, etc. are weak electrolytes.

The strength of the electrolyte is independent of solubility. For example, the strength of the electrolyte such as BaSO4 and CaCO3 is not necessarily related to the conductivity of the solution.

Strong acids, strong bases, and most salts are strong electrolytes.

Weak acids, weak bases, and a few salts are weak electrolytes.

Strong electrolytes and weak electrolytes are independent of solubility. For example, both BaSO4 and AGCL are poorly soluble in water, but their water-soluble parts are completely ionized, so they are both strong electrolytes.