Question

a. Define and distinguish between strong electrolytes and weak electrolytes. b. Give two examples of each type.

Short answer

Strong electrolytes completely dissociate in water, while weak electrolytes partially dissociate. Examples: Strong - NaCl, HCl; Weak - CH3COOH, NH3.

Step-by-step solution

- Define Electrolytes

Electrolytes are substances that dissociate into ions when dissolved in water, allowing the solution to conduct electricity.

- Define Strong Electrolytes

Strong electrolytes completely dissociate into ions when dissolved in water. As a result, they conduct electricity very well.

- Examples of Strong Electrolytes

Two examples of strong electrolytes are sodium chloride (NaCl) and hydrochloric acid (HCl).

- Define Weak Electrolytes

Weak electrolytes partially dissociate into ions in solution. Therefore, they conduct electricity, but not as well as strong electrolytes.

- Examples of Weak Electrolytes

Two examples of weak electrolytes are acetic acid (CH3COOH) and ammonia (NH3).

Key concepts

strong electrolytes

Strong electrolytes are substances that completely dissociate into ions when they dissolve in water. This means that every molecule of the substance breaks apart into positively and negatively charged particles, known as ions.

Because they fully dissociate, solutions of strong electrolytes are excellent conductors of electricity. The free-moving ions in the solution carry electrical current efficiently.

Examples of strong electrolytes include:

• Sodium chloride (NaCl): When NaCl dissolves in water, it breaks into Na⁺ and Cl^- ions.
• Hydrochloric acid (HCl): In water, HCl dissociates into H⁺ and Cl^- ions.

weak electrolytes

Weak electrolytes are substances that only partially dissociate into ions in an aqueous solution. This partial dissociation means that a significant proportion of the substance remains as intact molecules, with fewer ions available to conduct electricity.

Consequently, weak electrolytes conduct electricity, but much less efficiently than strong electrolytes. The fewer ions present in the solution mean less electrical current is carried.

Examples of weak electrolytes include:

• Acetic acid (CH₃COOH): In water, it partially dissociates into CH₃COO^- and H⁺ ions.
• Ammonia (NH₃): In water, it partially reacts to form NH₄⁺ and OH^- ions.

electrical conductivity in solutions

The ability of a solution to conduct electricity depends on the presence of charged particles, or ions. When an electrolyte dissolves in water, it releases ions that move freely and carry electric current.

Strong electrolytes produce a large number of ions, making their solutions highly conductive. Conversely, weak electrolytes produce fewer ions, resulting in poor conductivity.

Factors affecting the electrical conductivity of a solution include:

• The concentration of ions: Higher concentrations lead to better conductivity.
• The type of ions: Different ions have different abilities to conduct electricity.
• The temperature of the solution: Higher temperatures generally increase conductivity by increasing ion mobility.

ion dissociation

Ion dissociation occurs when a substance breaks down into its constituent ions upon dissolving in water. This process is crucial for the substance to be an effective electrolyte.

For strong electrolytes, dissociation is complete. Every molecule that dissolves separates into ions, making the process highly efficient.

Weak electrolytes, however, only partially dissociate. This incomplete dissociation results in a mixture of ions and intact molecules in the solution.

Key points to understand about ion dissociation include:

• It is essential for a substance to act as an electrolyte.
• Complete dissociation (strong electrolytes) means better conductivity.
• Partial dissociation (weak electrolytes) results in lower conductivity.