When rice is left in a pan of water overnight, what will happen to the rice? this process is called?

When rice is left in a pan of water overnight it is called soaking of the rice.

Soaking of rice is used to decrease cooking time, conserve fuel, minimize exposure to high temperature, and reduce stickiness. For some varieties, it can improve the texture of the cooked rice. For example, brown rice may be soaked in order to stimulate germination (germinated brown rice). In this case, soaking activates enzymes and enhances amino acids to improve the nutritional value of rice.