When a container containing a liquid is rotated, the liquid experiences a centrifugal force due to the rotation. This centrifugal force causes a change in the pressure energy of the liquid.

- **Kinetic Energy**: The kinetic energy of the liquid particles remains unchanged during the rotation of the container. The kinetic energy is determined by the velocity of the particles, which does not change unless external forces act upon the liquid.

- **Pressure Energy**: As the container rotates, the centrifugal force acts on the liquid particles, causing them to move away from the axis of rotation. This movement results in an increase in pressure energy. The pressure energy is directly related to the pressure exerted by the liquid, and when the liquid moves away from the axis of rotation, the pressure increases. This increase in pressure energy is a result of the centrifugal action and is responsible for the outward force experienced by the liquid.

- **Potential Energy**: The potential energy of the liquid does not change during the rotation of the container. The potential energy is determined by the height of the liquid above a reference point, and this height remains constant as the container rotates.

- **Energy due to Viscous Force**: The energy due to viscous force also remains unchanged during the rotation of the container. Viscous forces arise due to the internal friction between the layers of liquid as they move relative to each other. The rotation of the container does not affect the internal friction or the energy associated with it.

Therefore, the only energy that changes when a container containing a liquid is rotated is the pressure energy. The centrifugal force acting on the liquid particles causes an increase in pressure energy, resulting in an outward force experienced by the liquid.