What is unit cell ? What do you understand by simple, face centred and body centred unit cells?

What do you understand by unit cell of a crystal?

What do you understand by the terms: fuel-cell?

The unoccupied space in a body centred cubic unit cell is.

The number of atoms per unit cell in a simple cube, face - centred cube and body - centred cube are respectively :

Crystalline solid AB has face-centred cubic unit cell. Corners and the face centres of unit cell are occupied by atoms A. The edge centres and body centre of the unit cell are occupied by atoms B. If all the face-centred atoms along one of the axes are removed, then resulting chemical formula of the solid will become-

% of void space in body centred cubic unit cell.

What are the percentages of empty space in body-centred and face-centred cubic unit cells?

Distinguish between- (i) the hexagonal and monoclinic unit cells (ii) the face-centred and end-centred unit cells.

Define (a) simple or primitive unit cell (b) body-centred unit cell ( c) face-centred unit cell (d) end-centred unit cell.

A crystalline compound formed by elements A and B has facecentred cubic unit cell. The corners and the face-centred of the unit cell are occupied by A and B atoms, respectively. If one of the corner-atoms is found to be missing, then what would the formula of the compound be?