In an energy level diagram of a solid material, what is the region or separation between the conduction band and the valence band called?

What is the typical energy gap of semiconductors between the valence band and the conduction band?

What happens to the width of the forbidden energy gap in a semiconductor as its temperature increases?

A PN junction diode is reverse biased with 50 V, resulting in a reverse saturation current of 5 μA. If the operating temperature increases significantly, what will happen to the reverse leakage current?