Properties of Solutions Lab - Electrolytes vs. Non-Electrolytes

Properties of Solutions Lab - Electrolytes vs. Non-Electrolytes & The Effect of Conductivity of an Ionic Solution

Calculations

• Ionic Solution Conductivity: Compute slope calculations for conductivity plots for NaCl, CaCl2, and AlCl3.

Discussion Points

• Conductivity Lab Importance: Measures ionization in solutions, reflecting purity and chemical reactions.

Using the Periodic Table

• Sodium (Na): Group 1, Period 3; low ionization energy; forms Na⁺.

• Chlorine (Cl): Group 17, Period 3; high electronegativity; forms Cl⁻.

Atomic Structure

• Sodium: Protons: 11, Neutrons: 12, Electrons: 1s² 2s² 2p⁶ 3s¹.

• Chlorine: Protons: 17, Neutrons: 18, Electrons: 1s² 2s² 2p⁶ 3s² 3p⁵.

Valence Electrons

• Sodium: 1 valence electron (3s). Chlorine: 7 valence electrons (3s² 3p⁵).

Ionic Bond Formation

• Sodium transfers an electron to chlorine to form Na⁺ and Cl⁻, creating NaCl.

Chemical Reactions

• Oxidation: Na → Na⁺ + e⁻. Reduction: Cl + e⁻ → Cl⁻.

• Balanced Equation: 2 Na + Cl₂ → 2 NaCl (conservation of mass).

Energy Changes

• Sodium loses electrons; chlorine gains; energy released during NaCl formation.

Lattice Energy

• Lattice Energy = k(q1q2/r); NaCl has higher lattice energy than CsCl.

Dissociation in Water

• Water solvates NaCl into Na⁺ and Cl⁻ through ion-dipole interactions.

Classification of Solution

• Strong electrolytes: high conductivity; weak acids: lower conductivity; non-electrolytes: none.

Conclusions

• Strong electrolytes like sodium chloride significantly enhance conductivity in solutions, demonstrating ionic properties.