Hydrogen because it has only one proton and one electron
nitrogen
The smallest atom in the periodic table is hydrogen, not fluorine.
Atomic Radius gets greater down the periodic table and gets smaller to the right in the periodic table. This means, in order of atomic radius, that the five smallest elements are Helium, Neon, Fluorine, Oxygen, and Hydrogen in that order. Check all of it out at http://www.ptable.com/ under properties>radius
The smallest diameter in the periodic table belongs to the element helium, as it has the smallest atomic radius due to its high nuclear charge and the attraction between the electrons and the nucleus.
Lithium is the smallest element in the periodic table if Hydrogen and Helium are excluded.
Francium. The elements of the lower left hand side of the periodic table have the largest atomic radius. The upper right has the smallest.
Hydrogen
Hydrogen (H) - with a single proton and electron.
Hydrogen has the smallest atomic size of any element.
The smallest anionic radius is typically found on the right side of the periodic table in the halogen group (Group 17). This is because anions gain electrons to achieve a stable electron configuration, leading to a decrease in the atomic radius.
The period 4 element with the smallest atomic radius is chlorine, which has a greater number of protons in the nucleus pulling the electrons closer, making it smaller compared to other elements in the same period.
francium