What will the water in the glass tube most likely be if heating continues?

Rise higher in the tube.

Water has the tendency to evaporate especially when it is exposed to high temperature. This explains why water that you have been boiling for a long time may have the tendency to become fewer even if you know that you have placed a lot of water even before you started.

It is not possible for water to turn into solid when you are heating it. You need to place it in low temperatures so that it will start to become solid. It will definitely take the shape of its container this way. When heating, the water will just rise higher in the tube and may take the form of moist.