Solid State

A face-centered cubic unit cell contains 8 ‘X’ atoms at the corners of the cell and 6 ‘Y’ atoms at the faces. If the empirical formula of the solid is X_aY_b then, what is b/a?

An ionic compound (A⁺B^-) crystallizes in rock salt structure. If the ionic radii of A⁺ and B^- is 200pm and 400pm respectively, then calculate distance between nearest anions in Å.

The coordination number of an atom in a body- centred cubic structure is___________.

[Assume that the lattice is made up of atoms]

The distance between Na+ and Cl ions in solid NaCl of density 43.1g cm3 is ________*1010m. (Nearest Integer)

Percentage packing fraction of diamond is x (approximately), and the number of particle per unit cell is y. Then the value of x + y is

If X metal atoms occupying the corners, Y atom at cube centre and Z atoms at the centres of the edges, then if the co-ordination number of X w.r.t. Z is a and that of Y w.r.t. Z is b, then the value a + b is

Hexagonal unit cell is made up by AB.AB . . . packing, then shortest distance between two identical layers (say AA) in a unit cell of edge length x, is

In a solid AB, A atoms are in ccp arrangement and B atoms occupy all octahedral sites. If two atoms from the opposite face are removed, then the resultant stoichiometry of the compound is AxBy. The value of x is ___________(nearest integer)

Select the correct statements.
(A) Crystalline solids have long range order.
(B) Crystalline solids are isotropic.
(C) Amorphous solids are sometimes called pseudo solids
(D) Amorphous solids soften over a range of temperatures.
(E) Amorphous solids have a definite heat of fusion
Choose the most appropriate answer from the options given below:

Which amongst the following options is the correct relation between change in enthalpy and change in internal Energy?