Q. The atomic weights of two elements $A$ and $B$ are $40$ and $80$ respectively. If $x g$ of $A$ contains $y$ atoms, how many atoms are present in $2x g$ of $B$?
Some Basic Concepts of Chemistry
Solution:
Atomic mass
40
80
given weigh
x gram
2x gram
No. of mole
$\frac{x}{40}$
$\frac{2x}{80}$
But according to question $=\frac{x}{40}\times N_{A}=Y$
| Atomic mass | 40 | 80 | |
| given weigh | x gram | 2x gram | |
| No. of mole | $\frac{x}{40}$ | $\frac{2x}{80}$ |