# Questions tagged [atomic-radius]

For questions about the atomic radius - a measure of the size of an atom, usually the mean or typical distance from the center of the nucleus to the boundary of the surrounding "cloud" of electrons.

116 questions
Filter by
Sorted by
Tagged with
1answer
50 views

### How is most probable radius in quantum mechanical model equal to Bohr's radius in hydrogen atom

Most probable radius in 1s orbital for hydrogen electron is $\pu{0.529E-10 m}$ which is Bohr radius. But energy of electron in hydrogen atom is proportional to mean radial distance in atom. In this ...
0answers
29 views

### If most probable radius is inversely proportional to orbital quantum number, how is energy proportional to n+l

The closer an electron to the nucleus, the lesser the energy. Then why does a 3d electron have higher energy and be closer to nucleus than a 3s electron?
0answers
27 views

### According to quantum mechanical model does radial probability distribution show a maxima for lesser values of n ( shell number )

Here is a link where probability distribution graphs varying with radius for different azimuthal quantum numbers are compared to show that most probable radius is inversely proportional to l (...
1answer
21 views

### what is the use of finding out the radius of an atom [closed]

I happen to come across this, but what is the radius of an atom, velocity, KE, PE, etc.. actually used for? like the formula r=0.529n^2/z and so on
1answer
84 views

### Why is strontium(II) ion bigger than krypton atom?

$\ce{Sr^2+}$ is exactly the same as $\ce{Kr}$, in terms of electrons and orbitals. The only difference between the two, is that $\ce{Sr^2+}$ has a couple of extra protons in the nucleus (and probably ...
1answer
262 views

### Shielding effect of d electrons

In transition elements shielding effect is observed . Due to this zinc shows abnormality in atomic size. But at the same time we also say that gallium has same similar size as aluminium due to poor ...
0answers
25 views

1answer
1k views

### Why does the beryllium 2+ ion have a larger radius than a helium atom?

$\ce{Be^2+}$ has an ionic radius of $\pu{45 pm}$, while $\ce{He}$ has a radius of only $\pu{31 pm}$. If they are isoelectronic (they both have two elections in the $\mathrm{1p}$ orbital), and $\ce{Be}$...
0answers
235 views

### Why are the Covalent Radii of Ruthenium and Osmium So Similar?

Osmium and Ruthenium have covalent radii 144 and 146 respectively (according to Wikipedia). How are these values so similar when Osmium has 32 more electrons, with another filled p, s, and f orbital ...
1answer
484 views

### How to get ionic radii for coordination number 12?

I am studying $\ce{ABX3}$ perovskites, and I would like to calculate Goldschmidt tolerance factors for them. The $\ce{A}$ sites in these materials have a coordination number $12$. The Shannon's ...