About how many elements form all substances?
118 or 94 depending on how you look at it.
The first 94 elements are naturally occurring, and the elements from 95 to 118 are man made in laboratories.
In general, if you have a substance, (and it is not in a laboratory) then it is made of 94 possible elements. However, special man-made substances could, in theory, contain the other elements for a while.