Question

A solid has a structure in which, atoms of $W,O$ and $Na$ are located respectively at the comers, centre of edges and at the centre of the cubic lattice. The compound is

• A. $NaWO_2$
• B. $NaWO_3$
• C. $Na_2WO_3$
• D. $NaWO_4$

Answer 1

Answer: (B)

$NaWO_3$

Answer 2

Number of $W$ atoms present at each corner
$= 8 \times \frac{1}{8} = 1$
Number of $O$ atoms present at the centre of edges
$= 12 \times \frac{1}{4} = 3$
Number of $Na$ atoms present at the centre of cube $= 1$
$\therefore$ Formula of cube $= WO_3Na$ or $NaWO_3$