22.1 A Capillary Flow Analogy


Chemical Concepts Demonstrated: Order of a reaction, first-order kinetics

Demonstration:

Capillary tubing is attached a buret filled with water and clamped in a horizontal position.

Use a stop watch and record time vs. volume measurements as the water flows out of the buret.

Observations:

 

 

 

 

 

 

 

 

 

 

    Plotting volume versus time yields a slightly curved line.  Plotting the log of the volume versus the time yields a straight line.

Explanation:

    Because the log of the volume versus the time yields a straight line when plotted, the capillary flow appears to be first-order.