Conductivity

Conductivity

  • Submitted By: J0039472
  • Date Submitted: 02/09/2009 5:56 PM
  • Category: Science
  • Words: 497
  • Page: 2
  • Views: 330

Conductivities of Electrolyte Solutions

Conductivity can be measured by applying a rapidly oscillating field (>1 kHz) in an electrochemical cell and the mobility of ions in solution. No oxidation or reduction takes place in conductivity detection but charging and discharging of cell electrodes do occur. The fundamental measurement used to study conductivity is resistance of the solution. Under the precautions required the earlier experimental description should follow Ohm’s law in which where resistance equals the resistivity multiplied by the length between electrodes divided by the area of that geometry between electrodes. The resistivity, also called specific resistance, has the units of ohms/centimeters. Strong electrolytes are substances that completely ionize in solution and include ionic solids and strong acids. Weak electrolytes do not fully ionize in solution and they include Bronsted acids and bases.

Introduction

The purpose of this experiment is to determine the conductivities of electrolyte solutions. The process of determine whether strong or weak electrolytes exist in 0.1M KCL, 0.1M HCL, and Acetic Acid.

Procedure

Clean thoroughly a 100-mL volumetric flask, a 125-mL wide-mouth flask, and a 25-mL pipette. Rinse these with conductivity water. Rinse the 125-mL with two or three small aliquots of the stock solution, and then take not more than 100 mL of the solution. Rinse the pipette with two or three small aliquots form the flask, and then pipette exactly 25 mL of the solution form the flask into the volumetric flask. Make up to the mark with conductivity water and mix thoroughly. Set this aside for the next measurement and dilution. Use the solution remaining in the 125-mL flask for rinsing and filling the conductivity cell. When the measurement of resistance of the cell containing that solution has been completed, discard the remaining solution form the 125-mL flask and rinse with two or three aliquots of the new solution...