How to Identify Strong and Weak Electrolytes

Electrolyte is a material that dissociates into charged particles known as ions when it comes into contact with water. Cations are ions having positive charge. Anions are ions having negative charge. Simply put, an electrolyte is a substance that, when melted or dissolved in water, may conduct an electric current.

This includes the majority of soluble salts, acids, and bases dissolved in a polar solvent like water. When a substance dissolves, it separates into cations and anions which are distributed uniformly throughout the solvent. 

Electrolytes aren’t all substances that dissolve in water. Sugar, for example, dissolves swiftly in water but only as molecules, not as ions. Sugar is a compound that does not have an electrolyte. Because it ionizes, water is a weak electrolyte.

The essential components of salt dissociate when they are dissolved in a solvent such as water due to thermodynamic interactions between the solvent and solute molecules, a process known as “solvation.” 

Electrolysis is the process of disintegrating a molten or watery substance by putting an electric current through it. The main components of the electrolysis process are electrodes, electrolytes, and salt solution. The electrolyte is crucial to the process of electrolyte formation.

Classification of electrolyte

As chemists, we need to be able to immediately recognize which of these classifications a formula like HCl or NaOH belongs to, because we need to know what we’re working with (ions or compounds) while working with chemicals. 

For example, we need to know that a bottle labeled “NaCN” (salt) actually contains no NaCN but rather Na+ and CN–, or that a bottle labeled “HCN” (weak acid) contains mostly HCN but also a little amount of H+ and CN–.

Based on the degree of ionization, the electrolytes are divided into two groups.: 

1. Strong electrolytes – Electrolytes that are entirely dissociated into ions in solution are known as

strong electrolytes.

Because unionized molecules (electrolytes) are present in such small amounts, they can be neglected. They also have no application in the study of strong electrolyte ionization constants. Unlike weak electrolyte ionization equations, strong electrolyte ionization equations do not use double-headed arrows.

HCl + H2O → H3O+ + Cl–

HNO3 + H2O → H3O+ + NO3–

Examples of strong and weak electrolytes-

• Strong acid- eg, HCl, HI, HBr, HNO3, HNO3, HClO3
• Strong bases- eg, NaOH, KOH, LiOH, Ba(OH)2 
• Salts- eg NaCl, KBr, MgCl2, and many more

In solution or molten form, these electrolytes are totally ionized. As a result, these compounds only contain ions in a liquid or molten form. And also have a high conductivity of electricity.

2. Weak electrolytes- When a current is passed through a substance, it does not dissociate

entirely into ions.

Weak electrolyte molecules are in equilibrium with their ions in a solution. As a result, the ionization of the weak electrolytes equation is represented with double-headed arrows, suggesting that the reaction is reversible, as in-

NH3 + H2O ⇌ NH4++ OH–

CH3COOH + H2O ⇌ H3O++ CH3COO–

Examples of weak electrolytes-

• Weak acids- HF, H2CO3
• Weak bases- NH3

In a solution or molten state, these chemicals are partly ionized. Ions and un-dissociated molecules are present in these electrolytes. They have a low conductivity of electricity.

Difference between strong and weak electrolytes

CONCLUSION

Electrolytes are one of the most important components of electrochemical cells in science. Apart from that, they play an important role in the human body by maintaining electrolyte balance, which is necessary for the body’s proper functioning.