Question

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?

• A. y/2
• B. y/4
• C. y
• D. 2y

Answer 1

The correct option is C

y

No of moles of A = $\frac{x}{40}$ = y atoms

No of moles of B = $\frac{2x}{80}$ = $\frac{x}{40}$ = y

So, same moles will contain same no of atoms.