Question

In an ionic solid r₍₊₎ = 1.6 Å and r₍₋₎ = 1.864 Å. Use the radius ratio rule to the edge length of the cubic unit cell is ______ Å.

Options

• 2

• 4

• 6

• 8

Answer 1

In an ionic solid r₍₊₎ = 1.6 Å and r₍₋₎ = 1.864 Å. Use the radius ratio rule to the edge length of the cubic unit cell is 4 Å.

Explanation:

`"r"_((+))/"r"_((-)) = 1.6/1.864` = 0.858 ....[Body-Centred Cubic (BCC)]

∴ a = `(2(1.6 + 1.864))/sqrt3` = 4 Å