19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
The maximum radius of sphere that can be fitted in the tetrahedral hole of cubic close packing of sphere of radius r is.
For an ionic crystal of the general formula AX and coordination number 6, the value of radius ratio will be
If the radius of K⁺ and F– are 133 pm and 136 pm respectively, the distance between K⁺ and F– in KF is
Ferrous oxide has a cubic structure and each edge of the unit cell is 5.0 Å. Assuming density of the oxide as 4.0 g cm–3, then the number of Fe²⁺ and O₂– ions present in each unit cell will be
Which of the following fcc structure contains cations in alternate tetrahedral voids ?
Which defect causes decrease in the density of crystal
In a solid lattice the cation has left a lattice site and is located at an interstitial position, the lattice defect is
The correct statement regarding F-centre is
Zinc oxide loses oxygen on heating according to the reaction, heat ZnO Zn O 2e → It becomes yellow on heating because
Which kind of defect is shown by the given crystal?
Schottky defect in crystals is observed when
Which of the following defects are also called thermodynamic defects?
If ‘a’ stands for the edge length of the cubic systems: simple cubic, body centred cubic and face centred cubic, then the ratio of radii of the spheres in these system will be respectively. [CBSE AIPMT 2008]
The number of atoms per unit cell of bcc structure is [Kerala CEE 2009]
A compound of ‘A’ and ‘B’ crystallizes in a cubic lattice in which the ‘A’ atoms occupy the lattice points at the corners of the cube. The ‘B’ atoms occupy the centre of each face of the cube. The probable empirical f…
Three elements A, B and C crystallise into a cubic solid lattice. Atoms A occupy the corners, B atoms, the cube centres and C atoms, the face. The formula of the compound is [AMU 2009]
The appearance of colour in solid alkali metal halides is generally due to [RPMT 2010]
A solid is formed by two elements P and Q. The element Q forms cubic close packing and atoms of P occupy one third of tetrahedral voids. The formula of the compound is [AMU 2010]
Which of the following compounds shows both Frenkel and Schottky defects [AMU 2010]
Total number of voids in 0.5 mole of a compound forming hexagonal closed packed structure are
AB crystallises in a body-centred cubic lattice with edge 'a' equal to 387 pm. The distance between two oppositely charged ions in the lattice is (CBSE AIPMT 2010)
Number of unit cells in 4 g of X (atomic mass = 40) which crystallises in bcc pattern is (NA = Avogadro's number) (OJEE 2010) (a) A 0.1N (c) A 2 0.1N x (b) A 0.1N (d) A N x
If in a crystal lattice of a compound, each corner of a cube is enjoyed by sodium, each edge of a cube has oxygen and centre of cube is enjoyed by tungsten (W), then give its formula [Guj. CET 2011]
Which one of the following is a covalent crystal? [KCET 2011]
The metal crystallises with a face-centred cubic lattice. The edge of the unit cell is 408 pm. The diameter of the metal atom is (CBSE AIPMT 2012)