Respuesta :

Answer:

[tex]r_{cation}[/tex] = 0.2162 nm

Explanation:

The force of attraction can be written as:

[tex]F=\frac {K\times |Z_{cation}|e\times |Z_{anion}|e}{r^2}[/tex]

Where,  

K is the Coulomb's constant having value 9×10⁹ N. m²/C²

[tex]Z_{cation}[/tex]  is the charge on the cation

[tex]Z_{anion}[/tex]  is the charge on the anion

e is electronic charge = [tex]1.602\times 10^{-19}\ C[/tex]

r is the distance between the cation and anion and in bond, it is the sum of the ionic radius of cation and anion

So,

Given, F = [tex]1.12\times 10^{-8}\ N[/tex]

[tex]Z_{cation}=Z_{anion}=2[/tex]

Applying in the equation,

[tex]1.12\times 10^{-8}=\frac{9\times 10^9\times 2\times 1.602\times 10^{-19}\times 2\times 1.602\times 10^{-19}}{r^2}[/tex]

[tex]r^2=\frac{9\times \:10^9\times \:2\times \:1.602\times \:10^{-19}\times \:2\times \:1.602\times \:10^{-19}}{1.12\times \:10^{-8}}[/tex]

[tex]r^2=\frac{10^{-29}\cdot \:92.390544}{10^{-8}\cdot \:1.12}[/tex]

[tex]r=0.2872\times 10^{-9}\ m[/tex]

Also, 1 m = [tex]10^{-9}\ nm[/tex]

So, r = 0.2872 nm

Also,

[tex]r=r_{cation}+r_{anion}[/tex]

[tex]r_{cation}[/tex] = 0.071 nm

Thus,

[tex]0.2872\ nm=0.071\ nm+r_{anion}[/tex]

[tex]r_{cation}[/tex] = 0.2162 nm