Hcp and ccp are two different ways of three dimensional close packing:Will hcp and ccp structure for a given element have same density?

Hcp and ccp are two different ways of three dimensional close packing: What is the available space occupied in hcp and ccp?

Derive packing efficiency of ccp and hcp structure

Diamond is covalent solid in which carbon atoms are covalently bonded to form a three dimensional network structure: Give two difference in properties of covalent and molecular solids.

In crystalline solids, atoms or molecules are arranged in a regular and long range order fashion in a three dimensional pattern. T Q. An element (density 6.8 g/ cm^(3) ) occurs in bcc structure with cell edge of 290 pm. the number of atoms present in 200 g of element is:

Assertion : When an atom crystallizes in either fcc or hcp arrangement, density of the solid remains same in both the arrangements. Reason : Both fcc and hcp have same value of limiting packing fractions.

Density of a unit cell is the same as the density of the substance. So, if the density of the substance is known, we can calculate the number of atoms or dimensions of the unit cell. The density of the unit cell is related to its formula mass (M), number of atoms per unit cell (z), edge length (a in cm), and Avogadro's constant N_(A) , as rho=(zxxM)/(a^(3)xxN_(A)) Q. An element X crystallizes in a structure having an fcc unit cell of an edge 100 pm. if 24 g of the element contains 24xx10^(23) atoms, the density is