Home
Class 12
CHEMISTRY
A metal crystallizes into two cubic phas...

A metal crystallizes into two cubic phases, face-centred cubic and body-centred cubic, which have unit cell lengths `3.5` and `3.0 A`, respectively. Calculate the ratio of densities of fcc and bcc.

Text Solution

Verified by Experts

Density of a crystal is
`d = (Z xx "Formula mass of substance")/(N_A xx a^3)`
Now, for bcc, `Z = 4` and for bcc, `Z = 2`
`:. d("fcc") = (Z xx "Formula mass of substance")/(N_A xx (305 A)^3)`
`d("bcc") = (2 xx "Atomic mass of metal")/(N_A xx (3.0 A)^3)`
`:. (d("fcc"))/(d("bcc")) = 4/2 xx ((3.0)^3)/(3.5)^3 = 1.26`.
Promotional Banner

Topper's Solved these Questions

  • SOLID STATE

    MODERN PUBLICATION|Exercise COMPETITION FILE - OBJECTIVE TYPE QUESTIONS (A. MULTIPLE CHOICE QUESTIONS)|30 Videos

  • SOLID STATE

    MODERN PUBLICATION|Exercise COMPETITION FILE - OBJECTIVE TYPE QUESTIONS (B. MULTIPLE CHOICE QUESTIONS)|18 Videos

  • SOLID STATE

    MODERN PUBLICATION|Exercise REVISION EXERCISES (NUMERICAL PROBLEMS)(CBSE Qs)|6 Videos

  • POLYMERS

    MODERN PUBLICATION|Exercise Competition file (OBJECTIVE TYPE QUESTIONS) (C. MULTIPLE CHOICE QUESTIONS)(Integer Type Questions)|6 Videos

  • SOLUTIONS

    MODERN PUBLICATION|Exercise UNIT PRACTICE TEST|14 Videos

Similar Questions

Explore conceptually related problems

A metal crystallizes into two cubic phases, face-centred cubic and body-centred cubic, which have unit cell lengths 3.5 and 3.0 A , respectively. Calculate the ration of densities of fcc and bcc.

A metal crystallizes into two cubic systems - face centred cubic (fcc) and simple cubic (SC), whose unit cell lengths are 4.5Å and 1.501Å respectively. Calculate the ratio of densities of face centred cubic and Simple cubic.

In face-centred cubic unit cell :

In a face- centred cubic unit cell, the edge length is