logo

Ask Questions, Get Answers

 
X
 Search
Want to ask us a question? Click here
Browse Questions
Ad
Home  >>  AIMS  >>  Class12  >>  Chemistry  >>  Solid State
0 votes

Calculate the void fraction for the structure formed by A and B atoms such that A form hexagonal closed packed structure and B occupies 2/3 of octahedral voids. Assuming that B atoms exactly fitting into octahedral voids in the HCP formed by A

Can you answer this question?
 
 

1 Answer

0 votes
Total volume of A atom =$\large\frac{6\times 4}{3}$$\pi r_A^3$
Total volume of B atoms =$4\times \large\frac{ 4}{3}$$\pi r_B^3=4\times \large\frac{ 4}{3}$$\pi (0.414r_A^3)$
Since $\large\frac{r_A}{r_B}$$=0.414$ as B is in octahedral void of A
Volume of HCP = 24$\sqrt 2r_A^3$
Packing fraction =$ \large\frac{\Large\frac{6\times 4}{3}\pi r_A^3+4\times \Large\frac{ 4}{3}\pi (0.414r_A^3)}{24\sqrt2r_A^3}$
Void fraction = 1-0.7756 = 0.2244
Hence (A) is the correct answer.
answered May 30, 2014 by sreemathi.v
 

Related questions

Ask Question
student study plans
x
JEE MAIN, CBSE, NEET Mobile and Tablet App
The ultimate mobile app to help you crack your examinations
Get the Android App
...