The atomic mass of Silver is 107.8682 by the periodic chart I have here. That means that 1 mole of Silver masses
107.8682 grams if the Silver is pure.
I mole of any element like silver is also 6.022 X 10^23 atoms of silver.
!0^24 atoms is therefore more than a mole. You specified
2.3 x 10^24 atoms, so the number of moles will be
(2.3 X 10^24)divided by 6.022 X 10^23 = 3.819 moles
this number X 107.8682 grams/mole gives us 411.984 grams