A pure crystalline substance, on being heated gradually, first forms a turbid looking liquid and then the turbidity completely disappears. This behavior is the characteristic of substances forming.
It is a characteristic of liquid crystal.
In zinc blende structure, the coordination number of Zn2+ ion is
In the calcium fluoride structure, the coordination number of the cation and anion are respectively
When a certain crystal was studied by the Bragg technique using X – rays of wavelength 229 pm, an X – ray reflection was observed at an angle of 230 20’. What is the corresponding interplanar spacing? [sin (23020’) = 0.396]
Potassium fluoride has NaCl type structure. What is the distance between K+ and F- ions if cell edge is a cm?
Which defect causes decreases in the density of crystal?
The correct statement regarding F – centre is
Schottky defect in crystals is observed when
Frenkel defect is caused due to
An example of a non – stoichiometric compound is
Amorphous substances show
(i) short and long range order
(ii) short range order
(iii) long range order
(iv) have no sharp melting point