MHT CET202523 Apr 2025Evening ShiftChemistrySolid StateActual
Calculate the volume of bcc unit cell if radius of an atom present in it is 1.86 10⁻⁸ ~cm .
Options
- A5.391 10⁻²³ ~cm ^3
- B8.995 10⁻²³ ~cm ^3
- C7.951 10⁻²³ ~cm ^3
- D6.453 10⁻²³ ~cm ^3
Correct answer
C. 7.951 10⁻²³ ~cm ^3
Step-by-step solution
Body-centered cubic unit cell volume calculation In a BCC structure, atoms contact along the body diagonal, which spans 4r as it connects opposite corners through the center. For a cube with edge length a , the body diagonal equals 3 a , yielding the fundamental relationship: 4r = 3 a Solving for a : a = 4r 3 Substituting r = 1.86 10⁻⁸ cm: a = 4 1.86 10⁻⁸ 1.73205 4.295586 10⁻⁸ cm The cubic unit cell volume is then: V = a^3 = (4.295586 10⁻⁸)^3 7.925 10⁻²³ cm³ Among the options, 7.925 10⁻²³ cm³ most closely matches o