Number of elements present in the periodic table

Can someone tell me what is the total number of elements present in the periodic table? Some say it is 114, Others say it is 118 . There are still others who claim the number to be 122. Justify your answer giving reasons.

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As of this date, IUPAC has

As of this date, IUPAC has verified and now recognizes the claims for discovery of 112 elements (1 through 112); another five discoveries have been claimed by competent researchers and published in peer reviewed journals (113 through 116 and 118) but have not yet received verification and acceptance by IUPAC. Element 117 still eludes us because some of these discoveries involve multiple elements because of decay series, eg element 118 should decay into element 116 then to 114 then 112 and so on. This may account for the figure 118 you have read by someone who read that element 118 had been "discovered" and did not realize that that discover did not automatically include 117. There are a few claims for the discoveries of higher elements as traces in gold samples and such, but these claims have not, to my knowledge, been submitted to peer review and remain in the realm of cold fusion. Realizing that not all of the relevant research has been published or made publicly available (the intense interest in transuranic research in the US in the 50's and 60's was part of nuclear weapons research and many discoveries of that era were classified), the best answer to date is that so far the discoveries of 112 elements have been verified and that claims for 117 elements have been made through recognized channels. Not every claim of a discovery, even by a reputable research team, can be verified. A few years ago, Berkeley retracted a claim of discovery when they and other labs were unable to replicate the process claimed. In 1925, Nodak and others claimed the discovery of elements 75 and 43 in manganese samples; the first claim was accepted and rhenium is the name given by these researchers to element 75; no one could replicate the discovery of element 43, and later creation of the element by bombarding molybdenum produced a radioactive technetium, which many felt invalidated the earlier claim, but recently it has been suggested that Tc may well have been present in minute quantities as a decay product of uranium traces in the original samples used and that the 1925 claim may in fact have been valid after all.
Unlike religious "truths," scientific statements are always subject to revision, correction, or refutation, and that along with the best current research rather than some "correct" number may be the best answer to your question.

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