Question

How many atoms of helium are in a balloon, which contains 0.47 moles of the gas?

Answer 1

\[n=.47mol*6.022*10^{23}mol^{-1}=2.83*10^{23}\]

Answer 2

as they are sayin atoms multiple the ans by 2
as above given
2.83 x 2 x 10^23

Answer 3

Helium isn't a diatomic gas like Cl_2, it's just He. So no multiplication needed ;-)

Answer 4

but when we came to atom we always do that isntd?

Answer 5

Well, if a gas molecule consists of two atoms, then you have to multiply by 2. That would be the case for O_2, N_2, Cl_2 and so on. Helium and the other noble gases consist of only one atom. Thus, the number of moles equals the number of atoms.

Answer 6

ok... i get it thnx..