Ionic Conductivity

Question 1

What is Molar Conductivity?

Answer 1

Molar Conductivity (Λ) is the conductivity of an electrolyte when dissolved in solution.
𝚲 = 𝜿/𝒄
It is the sum of the anionic and cationic contributions from an electrolyte.
In general for a x:y electrolyte, AyBx

Question 2

What is Ionic conductivity?

Answer 2

Ionic conductivity is electrical conductivity due to the motion of ionic charge.

Question 3

Explain first factor that affects ionic molar conductivity?

Answer 3

1. Ion Size
   The smaller the size of the hydrated ion, the higher the ionic λ at infinite dilution λ^o.
   * Smaller size means more mobile

Question 4

Explain second factor that affects ionic molar conductivity?

Answer 4

2. Ion charge
   The larger the charge, the higher the ionic λ at infinite dilution λo (Al 3+&raquo_space; K + , SO42-&raquo_space; Cl -)
   * The bigger the ionic charge, the ‘more’ charge it can carry

Question 5

Explain third factor that affects ionic molar conductivity?

Answer 5

3. Proton Jumps
   Special case for H+ and OH

Question 6

Conductimetric Titrations

Answer 6

• Measure changes in solution conductivity as a reaction occurs.
• Takes advantage of different ionic conductivities
• More accurate and reproducible than using indicators (i.e. colour change).
• Shape of the conductimetric plot is dictated by ionic conductivities from ions present at
  each stage of the reaction.