Discussion
Calculate the lattice parameter of chromium assuming tight atomic bonding.
Answer: B
The lattice parameter is 2.880 Å.
In bcc the atoms touch along the body diagonal, which spans four atomic radii, or two diameters:
\[ \begin{aligned} \sqrt{3}\,a &= 4r = 2d \\ a &= \frac{2(2.494)}{\sqrt{3}} = 2.880\ \text{Å} \end{aligned} \]
1.442 Å is half of that, using the radius where the diameter belongs. 4.323 Å and 5.764 Å come from the wrong geometry, for example treating the face diagonal or the cube edge as the touching direction.
No comment is present. Be the first to comment.
Loading…
Post your comment
Please log in or register to post a comment.
Examination Categories
- SSC Exams
- Banking Exams
- Teaching Exams
- Civil Services Exams
- Railways Exams
- Engineering Recruitment Exams
- Defence Exams
- State Government Exams
- Police Exams
- Insurance Exams
- Nursing Exams
- Other Government Exams
- NRA CET
- PG Entrance Exams
- Campus Placement
- MBA Entrance Exams
- CUET and UG Entrance
- Judiciary Exams
- Regulatory Body Exams
- Software Development