Advertisements
Advertisements
प्रश्न
Which of the following lattices has the highest packing efficiency (i) simple cubic (ii) body-centred cubic and (iii) hexagonal close-packed lattice?
Advertisements
उत्तर १
Hexagonal close-packed lattice has the highest packing efficiency of 74%. The packing efficiencies of simple cubic and body-centred cubic lattices are 52.4% and 68% respectively.
उत्तर २
Packing efficiency of:-
Simple cubic = 52.4% bcc = 68% hcp = 74%
hcp lattice has the highest packing efficiency
संबंधित प्रश्न
Describe triclinic crystal lattice with the help of a diagram.
Define the following term: Primitive unit cells
Name the parameters that characterize a unit cell.
What is meant by the term ‘coordination number’?
An ionic crystal lattice has limiting value of radius ratio as 0.414 to 0.732; the co-ordination number of its cation is _______.
(A) 6
(B) 4
(C) 3
(D) 12
Calculate the number of atoms present in 2 gram of crystal which has face-centred cubic
(FCC) crystal lattice having edge length of 100 pm and density 10 gcm−3
An ionic crystal lattice has `r^+/r` radius ratio of 0.320, its coordination number is __
(a) 3
(b) 4
(c) 6
(d) 8
In the complexes `[Fe(CN)_6]^(3-)` and `[pt(en) (H_2O)_2(NO_2 (Cl)^(2+)]``the respective oxidation numbers of central metal atoms are
1) +3 and +4
2) +6 and + 4
3) +6 and +3
4) +3 and + 3
For a crystal of sodium chloride, state the type of lattice in which it crystallises.
i)
Consider the following cell reaction at 298 K: [3]
2Ag+ + Cd → 2Ag + Cd2+
The standard reduction potentials (E°) for Ag+/Ag and Cd2-/Cd are 0.80 V and -0.40 V respectively:
(1) Write the cell representation.
(2) What will be the emf of the cell if the concentration of Cd2+ is 0.1M and that of Ag+ is 0.2 M?
(3) Will the cell work spontaneously for the condition given in (2) above?
(ii)
What is a buffer solution? How is it prepared? Explain the buffer action of a basic buffer with a suitable example.
In a crystal of diamond:
- How many carbon atoms are present per unit cell?
- What type of lattice does diamond crystallise in?
- How many carbon atoms surround each carbon atom?
- How are they arranged?
The yellow colour in NaCl crystal is due to ____________.
Why ionic crystals are hard and brittle?
Crystals can be classified into basic crystal units, equal to ____________.
The lattice site in a pure crystal cannot be occupied by ______.
AB crystallises in a body centred cubic lattice with edge length' a' equal to 387 pm The distance between two oppositely charged ions in the lattice is:
A particular solid is very hard and has a high melting point. In solid state, it is a non-conductor and in molten state, it is a conductor of electricity. Classify the solid ______.
How many unit cells are present in a cube-shaped ideal crystal of NaCl of mass 1.00 g? [Atomic masses: Na = 23, Cl = 35.5]
