Entropy

[GT1]

If I have two tanks of 1 liter filled with water at the same temperature and I pour it to a 2 liter tank, would the total entropy of the system change? Why?
If I have a container which has a diaphragm at the middle, with the same gas (same temperature, same pressure etc.) from both sides of the diaphragm, at some moment the diaphragm is instantly removed, would the total entropy of the system change? Why?

[Q_Goest]

Entropy doesn't change. Look up "Gibbs Paradox".
If the partition is now removed, what should happen to the total entropy? Since the particles are identical, the total entropy should not increase as the partition is removed because the two states cannot be differentiated due to the indistinguishability of the particles.
Ref: http://www.nyu.edu/classes/tuckerman/stat.mech/lectures/lecture_6/node5.html