Question

If three elements $X,Y$ and $Z$ crystallizes in a $ccp$ lattice with the X atoms at the corner, $Y$ atoms at the cube centre and $Z$ atom at the edge centre the formula of the compound will be:

• A. $XYZ$
• B. $XY{Z}_2$
• C. $XY{Z}_3$
• D. $X_2{Y}_{2}Z$

Answer 1

The correct option is C $XY{Z}_3$

As X atoms are present at corners,

Number of X atoms = $8\times \frac{1}{8}$= 1

As the Y atom present at centre of cube

Number of Y atoms =1
As Z atoms are present on edge centre

Number of Z atoms = $12\times \frac{1}{4}=3$

$\therefore$ formula of the compound is $XY{Z}_3$

Option C is correct.