Name two salts that are used in black and white photography. Give equations of the reactions that occur when these are exposed to sun light

Name the salts that are used in black and white photography. Give reactions when they are exposed to light . Define the type of chemical reaction taking place.

Give equations for the reactions that occur when Magnesium metal is heated in air.

Give equations for the reactions that occur when Sodium metal is dropped into water.

Give equations for the reactions that occur when Sodium peroxide dissolves in water.

A chemical reaction which occurs in the presence of sun light is called-