Ask Questions, Get Answers

Want to ask us a question? Click here
Browse Questions
0 votes

A metallic element has a cubic lattice .Each edge of the unit cell is $2A^{\large\circ}$.The density of the metal is $2.5gcm^{-3}$.The unit cells in 200g of the metal are ?

$\begin{array}{1 1}1\times 10^{25}\\2\times 10^{15}\\3\times 10^{25}\\4\times 10^{25}\end{array} $

Can you answer this question?

1 Answer

0 votes
Edge length of the unit cell =$2A^{\large\circ}=2\times 10^{-8}cm$
Volume of the unit cell =$(2\times 10^{-8})^3cm^3$
$\Rightarrow 8\times 10^{-24}cm^3$
Mass of the unit cell =Volume $\times$ density
$\Rightarrow 8\times 10^{-24}\times 2.5g$
No. of unit cells in 200g of the metal =$\large\frac{\text{Mass of meta}}{\text{Mass of unit cell}}$
$\Rightarrow \large\frac{200}{8\times 10^{-24}\times 2.5}$
$\Rightarrow 1\times 10^{25}$
answered Aug 4, 2014 by sreemathi.v

Related questions

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