Final answer:
Silver with atomic number 47 is used in photographic films due to its chemical properties that allow it to reduce from silver compounds to create images.
Step-by-step explanation:
The element with atomic number 47 used to make photographic film is Silver (Ag). In the photographic process, images are created by silver reduced from radiation-sensitive silver compounds in the film emulsion. This shows silver's unique chemical properties that make it essential for the development of photographs.