What typically causes water to rise in a tank when heated?

The phenomenon that causes water to rise in a tank when heated is primarily due to thermal expansion. As water is heated, its temperature increases, leading to an increase in energy among the water molecules. This extra energy causes the molecules to move faster and spread apart, resulting in an increase in the water's volume. Therefore, the water occupies more space and causes the water level in the tank to rise.

Convection, on the other hand, refers to the movement of water as warmer, less dense water rises while cooler, denser water sinks. While convection currents are present in heated water and assist in the even distribution of temperature, the initial cause of water rising in a tank is thermal expansion, not simply the movement of water from convection.

Evaporation involves the transformation of water into vapor and does not directly contribute to the water level rising in a tank. Similarly, condensation relates to the process of vapor turning back into liquid, which would have the opposite effect on the water level. Thus, thermal expansion is the correct reason for the rise in water level when heated.