What is the distance between Na+ and Cl- in a NaCl crystal if its density is 2.165 g cm-3? NaCl crystallizes in fcc lattice.

For an ideal gas Density ρ = p x M/ RT F rom the given data, 5.46 = 2 x M/ 300 x R    ………(1) ALSO  ρSTP = 1 x M/ 273 x R    ………..(2) FROM...

A real crystal has some disorder due to presence of defects whereas ideal crystal has no disorder. 

Solution : Silver forms cubic close packing (ccp) , therefore the number of silver atoms per unit cell z=4 Molar mass of silver M=107.9 gmol−1 = 107.9×10−3kgmol−1 Edge length of unit cell a=408.6 pm = 408.6×10−12 Density d=(z.M)/(a3.NA) d=4×(107.9×10−3kgmol−1)/(408.6×10−12m)3(6.022×1023mol−1) =10.5×103kgm−3 d=10.5gcm−3

(i) There are 14 (8 from the corners + 6 from the faces) lattice points in face-centred cubic.  (ii) There are 14 (8 from the corners + 6 from the faces)...

Solution: Here, each interior angle = 165° Hence, each exterior angle = 180° - 165° = 15° As, measure of each exterior angle = 15° So, number of sides = 360°/15° = 24 Hence, number...

(d) : bcc - Points are at corners and one in the centre of the unit cell. Number of atoms per unit cell = 8 x 18 + 1 = 2. fcc...

(d) ? = 1256 ÷ (32 × 0.25) = 1256 ÷ 8 = 157

(b) ? = 7857 + 3596 + 4123/96 =15576/96 =162.25

(d) The series is as follows ×1 + (7 × 1), ×2 + (7 × 2 ), × 3 + (7 × 3), ×4 + (7× 4), × 5 + (7 ×...

About 1000 metres.