[toeknee2120]

I have a question about a practice problem I'm working on. The answers are either: increase, decrease, or no change. What is throwing me off is the fact that we're supposed to "ignore" solids in a equilibrium expression and how the question used the word amount versus concentration. I put my answers in italics and am pretty sure I'm right, but just need some clarification on the words used. I can't seem to find a decent explanation in my book or online.

Shown below is the chemical equation for the thermal decomposition of calcium carbonate.
CaCO₃(s)  CaO(s) + CO₂(g)         H°rxn = 175 kJ
How will the amount (not concentration) of CaCO3(s) change with the following stresses?

1) CO2(g) is removed. Decrease
2) CaO(s) is added.     Increase
3) The temperature is increased. Decrease
4) The volume of the container is decreased. No change

[Hunter2]

Should be correct.

[Dan]

4. is incorrect.