19,000+ solved questions for JEE Advanced, JEE Mains, NEET & IChO — with answers and expert explanations.
Ag crystallises as fcc. If radius of Ag is 144 pm then its density will be (a)10 g cm–3
A compound contains two types of atoms X and Y. It crystallises in a cubic lattice with atoms X at the corners of the unit cell and atoms Y at the body centre. The simplest possible formula of this compound is
In a solid ‘AB’ having the NaCl structure, ‘A’ atoms occupy the corners and face centres of the cubic unit cell but all the face-centred atoms along one of the axes are removed and ‘B’ atoms occupy octahedral voids, t…
In a compound, atoms of element Y form ccp lattice and those of element X occupy 2/3rd of tetrahedral voids. The formula of the compound will be
The unit cell of a binary alloy composed of A and B metals, has ccp. Structure with A atoms occupying the corners and B atoms occupying centres of each face of the cube. If during the crystallisation of this alloy, in…
Copper crystallises in fcc lattice with a unit cell edge of 361 pm. The radius of copper atom is
In a face centred cubic lattice, atom A occupies the corner positions and atom B occupies the face centre positions. If one atom of B is missing from one of the face centred points, the formula of the compound is
Which type of 'defect' has the presence of cations in the interstitial sites ?
Assertion : Glass is an amorphous solid. Reason : In glass, there is only short range order.
Assertion : The window glass of the old buildings is thick at bottom. Reason : Glass is a supercooled liquid of high viscosity and has the property to flow.
Assertion : Covalent crystals have a higher melting point. Reason : Covalent bonds are stronger than ionic bonds.
Assertion : Graphite is an example of tetragonal crystal system. Reason : For a tetragonal system, a = b c, α = β = γ = 90º.
Assertion : If density of CsCl (cubic structure) is 3.99 g/cm3, the distance between Cs+ and Cl- ions will be 357 pm [atomic mass of Cs = 133]. Reason : CsCl has bcc lattice.
Assertion : Packing in body centered cubic (bcc) structure is more efficient than in cubic closed packed (ccp) structure. Reason : 74% of the total space is occupied by the atoms in fcc structure while only 68% of the…
Assertion : If three elements A, B and C crystallize in a cubic solid lattice with A atoms at the corners, B atoms at the cube centre and C atoms at the centre of the faces of the cube, then the formula of the compoun…
Assertion : Co-ordination number of rock salt is 8. Reason : Limiting radius ratio for rock salt is between 0.414 and 0.732.
Assertion : In caesium chloride structure, Cl- ions are at the corners of a primitive cubic array and Cs+ ions fits into big central empty region in each Cl- array. Reason : The radius ratio r Cs r Cl is greater tha…
Assertion : Unlike Schottky defects, Frenkel defects don’t change the density of solids. Reason : These defects are basically point defects.
Assertion : In Schottky defects, electrical neutrality is maintained. Reason : Equal number of cation and anion vacancies are present.
Which of the following fcc structure contains cations in alternate tetrahedral voids ?
If the radius of K+ and F– are 133 pm and 136 pm respectively, the distance between K+ and F– in KF is
Edge length of a cube is 400 pm, its body diagonal would be
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)