The answer would be salt hydrolysis.
Salt that was made from the combination of weak and strong acid/base could be hydrolyzed and forming another substance. The hydrolysis process will separate the H2O into H+ and OH- and the weak part of the salt will take one of the ions(weak base will take OH-, weak acid will take H+). The result would be increased H+( or OH- ion, leading to change in pH of the solution.
D) The cell will expand and become turgid.
The plant cell will basically absorb all the water by osmosis and swell, but because it has a cell wall it will become turgid.
I believe a pot of water that is being heated by a electric burner. This is because the warmer water moves to the top and the cooler water moves down to the bottom of the pot. This causes a circular motion. The next example of convection heat is a hot air ballon rising and falling in the atmosphere. A radiator is also because the hot air is drawn out the top and the cooler air is drawn to the bottom.
