Atomic Radius

[Lauren Tindall]

How do you find the atomic radius of an element?

[Akshay Chellappa 1H]

The atomic radius of an atom is found by measuring the distance between the nuclei of two touching atoms. I believe that the atomic radius increases from right to left and from top to bottom on the periodic table.

[Christine Honda 2I]

You can calculate it using the distance between two nuclei of touching identical atoms, but as far as trends for atomic radius,
The size of an atom will decrease as you move from left to the right of a period.
The radius of atoms increases as you go down a certain group.

[Varadhan_3G]

Atomic radius refers to the distance between the nuclei of two identical atoms. I don't think atomic radius is something you can easily calculate unless already given distance (use equation r=d/2 where r is radius and d is internuclear distance); you would need to use x-ray/spectroscopic methods otherwise.

Atomic radius increases down the periodic table and decreases across the periodic table. It increases down the table because the number of occupied principle energy levels is increasing, and by extension the size of orbitals is increasing. It decreases across the periodic table because protons are being added to the nucleus of an atom, increasing the attraction between the surrounding electrons and the nucleus, condensing the atom.

Example problem:
The internuclear distance between the two hydrogen atoms in an H2 molecule is measured to be 74 pm. Therefore, the atomic radius of a hydrogen atom is 74/2, 37 pm.

[Abraham De Luna]

I believe that you find the atomic radius by measuring the distance between the nuclei of two touching atoms.

[Kelsey Ash 1D]

Atomic radius is the is half the distance between the centers of 2 neighboring atoms. Atomic radius decreases as you go across the periodic table from left to right and increases as you go down the periodic table.

[105311039]

Its the distance between two touching atoms and their nuclei.

[sarahsalama2E]

Atomic radius is 1/2 the distance between the centers of neighboring atoms, and increases as you go down a group and decreases across a period. It is important to know that that ionic radii also shows the same trends.