How many man made elements are there?
As of 2015, there are 23 man made elements. Technetium (atomic
no 43) is the only man-made element that comes before uranium (92),
the heaviest natural element.
Scientists have made 22 transuranium elements.
There are a further 4 - Ununtrium (113), Ununpentium (115),
Ununseptium (117) and Ununoctium (118) - whose existence has been
claimed. However, these are not yet recognised by International
Union of Pure and Applied Chemistry (IUPAC).