Helium has a density of 1.79 x 10-4 g/ml at standard temperature and pressure. a balloon has a volume of 6.3 liters. calculate the mass of helium that it would take to fill the balloon. be sure to follow significant figure rules when calculating the answer.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.

you need to have a picture of the atom that way we can answer it