Hot water tanks are sometime kept in a protective cover. The under-surface of the cover oftens gets dirty with dust from the floor. Suggest how the dust gets onto the under-surface of the cover.

How does the value of the equilibrium constant show that a reaction reaches equilibrium very quickly? (a) the equilibrium constant is large. (b) the equilibrium constant is small. (c) the equilibrium constant is zero. (d) the value of the equilibrium constant does not show how quickly a reaction comes to equilibrium.