Home
Class 12
CHEMISTRY
A solid A^(+)B^(-) has NaCl-type close-p...

A solid `A^(+)B^(-)` has `NaCl`-type close-packed structure. If the anion has a radius of `250` pm, what should be the ideal radius for the cation? Can a cation `C^(+)` having radius of `180` pm be slipped into the tetrahedral site of the crystal `A^(+)B^(-)`? Give reason for your answer.

Text Solution

Verified by Experts

The correct Answer is:
`No`
Limiting raidus ratio `(r_(o+))/(r_(ɵ)) = 0.414`
`r_(o+) = 0.414r_(ɵ)`
ideal radius for the cation `= 0.225(r_ɵ)`
`= 0.225 xx 250 = 56.25` pm
Since the size of the cation (`180` pm) is much larger than the ideal raidus (`56.25` pm), the cation introduced in `TV` of the crystal, pushes the anions outwards and the anions do not remain close packed. The new structure will be unstable.
Promotional Banner

Similar Questions

Explore conceptually related problems

A solid A^+ B^- has NaCI type close packed structure. If the anion has a radius of 241.5 pm, what should be the ideal radius of cation ?

A solid A^(o+)B^(ɵ) has NaCl -type close-packed structure. If the radius of the cation is 90 pm, calculate the probable range of the radius of the anion.

A solid AB has NaCl structure. If the radius of the cation A is 100 pm, what is the radius of anion B ?

A binary solid A^+B^-) has a rock structure. If the edge length is 400 pm and radius of cation is 75 pm, the radius of anion is

An ionic solid A^(o+)B^(Θ) crystallizes as an fcc structure. If the edge length of cell is 508 pm and the radius of anion is 144 ppm, the radius of cation is

If the close-packed cations in an AB -type solid with NaCl structure have a radius of 75 pm. What would be the maximum and minimum sizes of the anions filling the voids?

Aluminium crystallies in a cubic close packed structure. Radius of the atom in the metal is 125 pm. (i) What is the length of the side of the unit cell ? (ii) How many unit cells are there in 1 cm^(3) of aluminium ?

An ionic solid A^(o+)B^(Θ) crystallizes as an bcc structure. The distance between cation and anion in the lattice is 338 pm . The edge length of cell is

In a crystallizes solid, anions B are arranged in cubic close packing, cations A are equally distributed between octahedral and tetrahedral voids, what is the formula of the solid?

The elements Li, Na and K, each having one valence electron, are in period 2, 3 and 4 respectively of modern periodic table. (1) In which group of the periodic table should they be? (ii) Which one of them is least reactive ? (iii) Which one of them has the largest atomic radius? Give reason to justify your answer in each case.