Question

A compound formed by elements $X$ and $Y$ crystallizes in the cubic structure, where $X$ atoms are at the corners of a cube and $Y$ atoms are at the centres of the body. The formula of the compound is

• A. $XY$
• B. $XY_2$
• C. $X_2Y_3$
• D. $XY_3$

Answer 1

Answer: (A)

$XY$

Answer 2

Number of $X$ atoms at the corners $=8$

N?mber of $X$ atoms per unit cell $=8 \times \frac{1}{8}=1$ atom

Number of $Y$ atoms at the centre of the body $=1$ atom
Hence, the formula of the compound is $XY$.