X – ray analysis shows that the unit cell length in NaCl is 562.8 pm. Calculate the density you would expect on this basis,
NA = 6.023 × 1023 mol-1.
2.179 g cm-3
= 2.179 cm-3
The unit cell of aluminum is a cube with an edge length of 405 pm. The density of aluminum is 2.70 g cm-3. The type of unit cell is
A binary solid X+ Y- has a zinc blende structure with Y- ions forming the lattice and X+ ion occupying 25% tetrahedral sites. The formula of the solid is
Gold (at wt. 197g mol-1) crystallises is a cubic closest packed structures (the face – centred cubic) and has a density of 19.3g/cm2. Its atomic radius is
Calcium metal crystallizes in fcc lattice with edge length 556 pm. Calculate the density (in g cm-3) of metal if it contains 0.2% Schottky defects.
Which of the following statements about amorphous solids is incorrect?
An alloy of Cu, Ag and Au is found to have Cu forming the simple cubic closed packed lattice. If the Ag atoms occupy the face centres and Au is present at the body centre, the formula of the alloy will be
If the radius ratio is in the range of 0.414 – 0.732, then the coordination number will be
Quartz is a crystalline variety of
If the distance between Na+ and Cl- ions in NaCl crystal is ‘a’ pm what is the length of the cell edge?
A crystalline solid