When an electron in an excited Mo atom falls from L to the K shell, an X-ray is emitted. These X-rays are diffracted at angle of 7.75o by planes with a separation of 2.64Å. What is the difference in energy between K-shell and L-shell in Mo assuming a first-order diffraction. (sin7.75o=0.1349)

(1) 36.88 ×1015J

(2) 27.88×1016J

(3) 63.88 ×1017J

(4) 64.88×1016J

Concept Questions :-

Introduction and Type of Crystal System
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


Which is the incorrect statement?

(a) FeO0.98 has non-stoichiometric metal deficiency defect

(b) Density decreases in case of crystals with Schottky's defect

(c) NaCI(s) is insulator, silicon is semiconductor, silver is conductor, quartz is piezoelectric crystal

(d) Frenkel defect is favoured in those ionic compounds in which sizes of cation and anions are almost equal

Concept Questions :-

Imperfections in Solids
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


In calcium fluoride, having the fluorite structure, the coordination numbers for calcium ion (Ca2+) and fluoride ion (F-) are

(a) 4 and 2                   (b) 6 and 6

(c) 8 and 4                   (d) 4 and 8

Concept Questions :-

Introduction and Type of Crystal System
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


Lithium has a bcc structure. Its density is 530 kg m-3 and its atomic mass is 6.94 gmol-1. Calculate the edge length of a unit cell of lithium metal.

(NA=6.02 x1023 mol-1)

(a) 352 pm
(b) 527 pm
(c) 264 pm
(d) 154 pm

 

Concept Questions :-

Density/Formula/packing fraction/ Semiconductors
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


The ionic radii of A+ and B- ions are 0.98 x 10-10 m and 1.81 x10-10 m.  The coordination number of each ion in AB is.

(a) 4

(b) 8

(c) 2

(d) 6

 

Concept Questions :-

Voids and radius ratio/coordination number
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


A given metal crystallises out with a cubic structure having edge length of 361 pm. If there are four metal atoms in one unit cell, what is the radius of one atom ?

(a) 40 pm

(b) 127 pm

(c) 80 pm

(d) 108 pm

Concept Questions :-

Density/Formula/packing fraction/ Semiconductors
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


The correct statement regarding defects in the crystalline solid is

(a) Schottky defects have no effect on the density of crystalline solids

(b) Frenkel defects decreases the density of crystalline solids

(c) Frenkel defcct is a dislocation defect

(d) Frenkel defect is found in halides of alkaline metals

Concept Questions :-

Imperfections in Solids
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


The vacant space in bcc lattice cell is ;


(a) 26%

(b) 48%

(c) 23%

(d) 32%

Concept Questions :-

Voids and radius ratio/coordination number
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


if a is the length of the side of a cube, the distance between the body centered atom and one corner atom in the cube will be :-

(a) a   (b) a   (c)√3 a   (d)√3 a
    √3          √3            4            2

Concept Questions :-

Introduction and Type of Crystal System
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level:


A metal cryszallizes with a face-centered cubic lattice. The edge of the unit cell is 408 pm.
The diameter of the metal atom is
(a) 288 pm
(b) 408 pm
(c) 144 pm
(d) 204 pm

Concept Questions :-

Introduction and Type of Crystal System
To view Explanation, Please buy any of the course from below.
High Yielding Test Series + Question Bank - NEET 2020

Difficulty Level: