Solid State Tes...

Pyrite, $$FeS_2$$ crystallises in a cubic unit cell with a cell edge of 0.54 nm. The density of pyrite is $$5.02 g/cm^3$$. How many $$Fe^{2+}$$ and $$S^{2-}_2$$ ions are present in a single unit cell?
(S = 32, Fe =56u)

The unit cell in a body centred cubic lattice is given in the figure. Each sphere has a radius, $$r$$ and the cube has a side, $$a$$.
What fraction of the total cube volume of empty?

The closest-packing sequence $$ABAB .....$$ represents

The crystal system of a compound with unit cell dimensions $$a = 0.387, b = 0.387, c = 0.504\ nm$$ and $$\alpha = \beta = 90^{\circ}$$ and $$\gamma = 120^{\circ}$$ is:

Which of the following statements is not correct?

Example of unit cell with crystallographic dimensions $$a\neq b \neq c, \alpha = \gamma = 90^{\circ}, \beta \neq 90^{\circ}$$ is:

In which of the following type of lattices, the coordination number is 4?

Close packing is maximum in the crystal lattice of

A match box exhibits:

The formula for determination of density of a cubic unit cell is: