How many grams of sodium wil have the same number of atoms as 6 grams of magnesium
`("Given Na"=23u, Mg=24u)?`

Explanation

24g of magnesium have atoms `N_(A)=6.022xx10^(23)`
`"6 g of magensium have atoms"=6.022xx10^(23)xx((6g))/((24g))`
`=1.505xx10^(23)`
`6.022xx10^(23)"atoms of sodium have mass"=23g`
`1.505xx10^(23)"atoms of sodium have mass"=(23g)xx(1.505xx10^(23))/(6.022xx10^(23))`
=5.75g