Question

The first order reflection of a beam of  X – rays of wavelength  from the (210) plane of a crystal of the simple cubic type, occurs at an angle of 11.290, the length of the unit cell is

Solution

Correct option is

8.794 × 10-8 cm

 

 

1 × (1.54 × 10-8) = 2 × d × sin 11.29

                         d = 3.933 × 10-8 cm  

   

       

                            

                              = 8.794 × 10-8 cm

SIMILAR QUESTIONS

Q1

The density of solid argon is 1.65 g/mL at –233oC. If the argon atom is assumed to be sphere of radius 1.54 × 10–8 cm, what percentage of solid argon is apparently empty space?(At wt of Ar = 40).

Q2

A compound CuCl has fcc structure. Its density is 3.4 g cm–3, what is the length of unit cell?

Q3

A metal crystallizes into two cubic phases fcc and bcc whose unit cell lengths are 3.5 and 3.0 Å respectively. What is the ratio of densities of fcc and bcc?

Q4

The radius of a divalent cation M2+ is 94 pm and that of divalent anion X2–is 146 pm. Thus, M2+ X2– has

Q5

MgO has a structure of NaCl, the coordination number of O2– in MgO is

Q6

If NaCl is doped with 10–3 mol% of SrCl2, calculate the concentration of cation vacancies

Q7

The composition of a sample of wustite is Fe0.93 O. What percentage of the iron is present in the form of  Fe III?

Q8

A solid AB has the NaCI structure. If radius of cation A+ is 120 pm, the maximum possible value of the radius of the anion B- is

Q9

CsCl crystallizes in a cubic lattice that has a Cl- at each corner and Cs+ at the centre of the unit cell. What is the value of edge length a of the cube?  

Q10

 

KCI crystallises in the same type of lattice as does NaCI.

   

The ratio of the side of the unit cell for NaCI to that for KCI is