Chem 2/5 Labs  FS/97
#404-LeChatelier's Principle
Postlab


1.	The following reaction is endothermic

		Heat  +  2SO3(g) <==>  2SO2(g)  +  O2(g)

	a.	Write the equilibrium expression for this reaction.





Explain the effect on the position of the equilibrium given the following changes 
to the system.

b.	The volume of the system is decreased. (compressed at constant temperature)



c.	An inert gas is pumped in without changing the volume.



2.	Cobalt chloride is used in inexpensive humidity gauges.  
Explain how cobalt chloride can be used to detect high/low humidity in the air.






3.	In an ___________________ reaction, heat is released to the surroundings.

4.	In an ____________________ reaction, heat is absorbed by the system.