The atomic weights of two alements A and B are 40 and 80 reapectively. If x g of A contains y atoms, how many atoms are present in 2x g of B?

Options

A. `y/2`
B. `y/4`
C. y
D. 2y

Answer

C

Explanation

Number of moles of `A=x/40`
Number of atoms of `A=x/40xx` Avogadro no. `=y` (say)
or `x=(40 y)/("Avogadro no.")`
Number of moles of `B=(2x)/80`
Number of atoms of B
`=(2x)/80xx" a.v. no."=2/80xx(40y)/("Av. No.")xx" Av. no."=y`