SOLID STATE

The coordination number of atoms in a cubic closed-packed is ________.

• 2

• 8

• 12

• 6

The coordination number of atoms in a body-centred cubic structure is ________.

• 4

• 8

• 6

• 12

The type defect observed in ionic crystals which large difference in the size of ions is:

• Interstitial defect

• Frenkel defect

• Schottky Defect

• Stoichiometric Defect

A mixed oxide has ccp arrangement in which the cations 'X' occupy 1/3rd of octahedral voids and the cations 'Y' occupy 1/3rd of tetrahedral voids.The formula of oxide is:

• X ₂Y ₃O ₂

• XY ₃O

• X ₂YO ₃

• XY ₂O ₃

An element with molar mass 64 gmol ^-1 and density 6.6 g cm ^-3 forms a cubic unit cell.The edge length of unit cell is 4 x 10 ^-8cm.The type of cubic unit cell formed is ?

• fcc

• ccp

• bcc

• hcp

A solid is made up of 2 elements P and Q. Atoms Q are in ccp arrangement,while P atoms occupy all the tetrahedral sites.The formula of the compound is:

• PQ ₂

• P ₆Q ₄

• P ₂Q

• PQ

A compound is formed by two elements X and Y. Atoms of the element Y (as anions) make ccp and those of the element X (as cations) occupy all the octahedral voids. The formula of the compound is :

• X ₂Y

• X ₄Y

• XY

• XY ₂

Atoms of element B form hcp lattice and those of the element A occupy 2/3rd of tetrahedral voids. The formula of the compound formed by the elements A and B is:

• A ₄B ₃

• A ₂B

• A ₃B ₄

• AB

An element with molar mass 2.7 x 10 ^-2 kg mol ^-1 forms a cubic unit cell with edge length 405 pm. If its density is 2.7 x 10 ³ kg m ^-3,the nature of cubic unit cell is :

• hcp

• ccp

• bcc

• fcc

Name the defects noticed when a solid is heated.

• Frenkel Defect

• Interstitial Defect

• Schottky Defect

• Vacancy Defect