Most Big Atom

[patelashish]

What is the Most Big Atom and Why it is so ?

[gen2]

The largest atom is an atom of the element with the highest atomic number. It is the largest because it has more protons, neutrons and electrons than any other.

Which one it is depends on your definition of existence. The elements with the largest atomic numbers are man-made and only hang together for a tiny fraction of a second before decaying into lesser elements.

[boobesque]

the atomic number is the number of protons. atomic mass is the total number of necleons. so the element with the highest atomic mass would be the largest atom which would be lawrencium (lw) with an atomic number of 103 and an atomic mass of 260.11

[gen2]

boobesque, Lawrencium (103) was discovered when I was at school. Many more elements have been discovered/created since then though not all have been given names, just numbers like Ununbium (112) discovered in 1996. These elements have extremely short half lives and are generally considerd to be 'synthetic'. That is why I included the caveat of the need to settle on a definition of existence of an element or atom.

Incidentally, Lawrencium is also considered to be a synthetic radio-active element.

[Gef]

gen, I agree with what you say about "man-made" elements but all up to atomic number 111 have been named.

http://www.chemsoc.org/VISELEMENTS/pages/perta ble_fla.htm

[nightmare]

gen2

The higher the atomic number, the larger the positive nuclear charge. Therefore as the atomic no. increases., the outermost electrons are more strongly attracted to the nucleus, resulting in a general slight decrease in atomic radius with increasing atomic no., for atoms in the same period.
It is not as straightforward as it seems.