Hi all. Here is the question:
Consider the following systems:
a) a container that is half filled with alcohol, stoppered and allowed to stand for several days
b) crystals of potassium permanganate that are dissolved in water until the water becomes a uniform purple colour and a constant amount of cyrstal remains in the container
c) an ice cube in a beaker of water in a normal classroom
d) moth balls that are place in a an empty flask that is stoppered and allowed to stand for several days
Which of the above are at an equilibrium state?
i) a and b only
ii) a, b and d only
iii) b and c only
iv) a, b, c, and d
So I know that a) is in an equilibrium state. Beyond that I am a bit stumped. I don't think b) or c) are because they are not in a closed system. Option d) is in a closed system but I don't think there is a reaction or phase change occuring in this case. That means none of the possible options agree with me. Where am I going wrong?