ELECTROCHEMISTRY (FACTORS AFFECT ING molar conductivity)
Molar conductivity, denoted by the symbol Λm, is a measure of a solution's ability to conduct electricity, specifically, the conductance of a solution containing one mole of the electrolyte placed between electrodes with a unit area and a distance of one unit length. It is influenced by several key factors:
**1. Concentration of the electrolyte:**
* Molar conductivity generally **increases with dilution** (decreasing concentration). This is because as the solution is diluted, the distance between ions increases, reducing the frequency of collisions and allowing them to move more freely under the influence of an electric field, thus, enhancing conductivity.
[Image of Molar conductivity vs concentration graph]
**2. Nature of the electrolyte:**
* The **degree of dissociation** of the electrolyte plays a crucial role. Strong electrolytes, which dissociate completely in solution, have a higher number of ions per unit volume, leading to higher molar conductivity compared to weak electrolytes, which dissociate only partially.
* The **size and charge of the ions** also influence conductivity. Smaller and highly charged ions have greater mobility and contribute more significantly to conductivity than larger or less charged ions.
**3. Temperature:**
* Molar conductivity generally **increases with temperature**. This is because as the temperature rises, the solvent molecules move faster and collide with the ions more frequently, imparting kinetic energy to the ions and increasing their average velocity. This, in turn, enhances their ability to carry current, leading to higher conductivity.
It's important to note that the relationship between molar conductivity and concentration is not linear. As the concentration approaches zero (infinite dilution), the molar conductivity reaches a limiting value, known as **limiting molar conductivity (Λ⁰m)**. This value represents the maximum conductivity achievable for the electrolyte and is independent of concentration.
