Question

how many present known elements​

Answer 1

118 known elements

There are now 118 known elements. In this context, "known" means observed well enough, even from just a few decay products, to have been differentiated from other elements.

Answer 2

118 known elements

There are now 118 known elements. In this context, "known" means observed well enough, even from just a few decay products, to have been differentiated from other elements.

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