InterviewSolution
Saved Bookmarks
InterviewSolution
| 1. |
A solid has a structure in which `X` atoms are located at cubic corners of unit cell, `O` atom are at the edge centres and `Y` atoms at cube centre. Then the formula of compound is `X_(a)Y_(b)O_(c)` If two atoms of `O` missing from any of two edge centres per unit cell, then the molecular formula is `X_(a)Y_(b)O_(z)`. Then, find the value of `(x + y + z) - (a + b+ c)`. |
|
Answer» Correct Answer - 4 a. Number of X atoms `=8xx(1)/(8)=1`/unit cell. Number of Y atoms=1/unit cell. Number of O atoms `=12xx(1)/(4)=3` /unit cell Formula is : `XYO_(3)rArrX_(a)Y_(b)O_(c)` b. Number of O atoms missing from two edge centers per unit cell `=2xx(1)/(4)=(1)/(2)` /unit cell Number of O atoms left `=3-(1)/(2)=2.5`/unit cell Formula is `XYO_(2.5)rArrX_(2)Y_(2)O_(5)rArrX_(x)Y_(y)O_(z)` `therefore` Total value of `(x+y+z)-(a+b+c)=(2+2+5)-(1+1+3)=4` |
|