Question

what is atomic radii?

Answer 1

The term atomic radius is generally used in reference to the size of an atom. Atoms are generally regarded as spherical in shape. Atomic radius is therefore the distance between the centre of the nucleus and the outermost shell of an isolated atom.

For example, when we say that the atomic radius of hydrogen atom is 37 pm (picometre, 1 pm = 10^ –12m), it means that the distance between hydrogen nucleus and the outermost shell is 37 pm. Greater the atomic radius, more is the size of the atom. The atomic radius increases down the group and decreases across a period.

Answer 2

atomic radii means radious of atom..
for eg.
H= 0.037nm
C=0.077nm
....
.....
...
the size of atom is indicated by irs radius which is called atomic radii.