How can one be so sure that the elements listed in the periodic table are the only ones that exist?

Question

parthkohli · Answer

@Preetha Can you please explain? Thanks!

anonymous · Answer

Because there are no fractional number of protons.

anonymous · Answer

atleast now we are pretty sure that there cannot be any new elements that can popup between the already known elements. this is not the case during mendleev days. he predicted some elements to exist between known elements based on trends in properties

parthkohli · Answer

Has there been any amendment in the periodic table ever since its creation?

anonymous · Answer

and whatever he predicted were discovered later on, but now other than creating new synthetic elements, there are no new natural elements thaat can exist, if there were new elements also, they would have disappeared by now due to radioactive decay

anonymous · Answer

Plenty.

anonymous · Answer

many amendments were there, initial one was based on atomic mass

parthkohli · Answer

And now, how are we so sure again, that no amendment will be there in the future?

anonymous · Answer

then mosely came and told us that an element can be pinpointed based on its positive charge (nucleus charge)

anonymous · Answer

"Because there are no fractional number of protons."

anonymous · Answer

then, we rearranged periodic table based on atomic number, and atomic number is +ve integer, so there cannot be any new elements between known elements

parthkohli · Answer

Hmm... I don't know Chemistry at all. :|

parthkohli · Answer

I don't know which one is the better answer.

anonymous · Answer

do we have two different answers here, both cliffsedge and me saying the same !

anonymous · Answer

it helps to know that some elements we can CREATE in lab, not all elements are natural

anonymous · Answer

and not all elements we can create in lab, those elements we create in lab are mostly unstable with very less half life times

anonymous · Answer

and some elements existed few billion years ago dont exist anymore, we never knew about them becoz they got decayed

anonymous · Answer

You get my vote, Sara. You explained in more detail.

anonymous · Answer

this is the module i finished just recently and moved to compounds :)