Explore BrainMass

Half-life and Periodic Trends

Because the time it takes for a reaction to actually reach equilibrium is infinite, scientists have used the estimate that after ten half-lives (or ten half-times) the reaction is completed (i.e., the reaction has reached equilibrium). Chlorine gas and solid sodium metal react to produce sodium chloride. If you place one mole of chlorine gas in an evacuated, 1-L container with a large excess of sodium and maintain the flask at 25 degrees celcius, the reaction follows first order kinetics. After 25 minutes , the pressure in the flask is found to be 5.3824 atm. Determine the total time it would take for the reaction to come to completion (i.e., reach ten half-times). R=0.0820578 L atm/Deg mol

A 0.1677m aqueous solution of acetic acidhas a freezing point of -0.3152. The calculated freezing point is actually -0.3119. Explain this difference

Solution Preview

Hello and thank you for posting your question to Brainmass!

The solution is attached below in two files. the files are identical in content, only differ in format. The first is in MS Word XP Format, while the other is in Adobe pdf format. Therefore you can choose the format that is suitable to you.

Here is how to approach the first ...

Solution Summary

The solution gives 245 words of guidance on the steps to take to determine the time a given reaction will take to reach completion. Links for further clarification are included.